Controlling ultraviolet intensity over a surface of a light sensitive object

ABSTRACT

An approach for controlling ultraviolet intensity over a surface of a light sensitive object is described. Aspects involve using ultraviolet radiation with a wavelength range that includes ultraviolet-A and ultraviolet-B radiation to irradiate the surface. Light sensors measure light intensity at the surface, wherein each sensor measures light intensity in a wavelength range that corresponds to a wavelength range emitted from at least one of the sources. A controller controls the light intensity over the surface by adjusting the power of the sources as a function of the light intensity measurements. The controller uses the light intensity measurements to determine whether each source is illuminating the surface with an intensity that is within an acceptable variation with a predetermined intensity value targeted for the surface. The controller adjusts the power of the sources as a function of the variation to ensure an optimal distribution of light intensity over the surface.

REFERENCE TO RELATED APPLICATIONS

The present patent application is a continuation-in-part of U.S.application Ser. No. 15/711,291, filed on 21 Sep. 2017, which claims thebenefit of U.S. Provisional Application No. 62/403,003, filed on 30 Sep.2016, each of which is hereby incorporated by reference in its entiretyto provide continuity of disclosure. The application is also related toU.S. application Ser. No. 15/678,456, filed on 16 Aug. 2017, U.S.application Ser. No. 15/962,574, filed on 25 Apr. 2018, and U.S.application Ser. No. 16/205,896, filed on 30 Nov. 2018, each of which ishereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates generally to controlled lightingenvironments, and more particularly, to a smart lighting system thatutilizes light sensors to detect light intensity at a surface of a lightsensitive object, and a controller that receives feedback from the lightsensors and controls the light intensity over the surface to within anacceptable variation in order to attain an acceptable light intensitydistribution.

BACKGROUND ART

A plant is one type of light sensitive object that can be grown in acontrolled light environment. Growing plants under controlled conditionssuch as in greenhouses, growth cabinets or warehouses, generally entailsmonitoring the plant environment and controlling parameters such aslight, water vapor pressure, temperature, CO₂ partial pressure, and airmovement, in order to adjust the microclimate of the environment foroptimizing growth and photosynthesis in an empirical manner. Plantattributes such as quantitative morphological, physiological andbiochemical characteristics of at least a part of the plant may also bemodulated during the monitoring of the plant environment and controllingof environment parameters.

Having the ability to determine the physiological condition of a plantor a group of plants is useful in implementing photosynthetic responsesinto climate control algorithms or models that can be used in acontrolled light environment. Optimization of photosynthesis of crops orplant material can be achieved through careful and planned manipulationsof growth conditions based on in-situ monitoring of relevantphotosynthetic processes. Relevant and short-term plant responses areinvolved in the definition of growth requirements not only throughclimate control, but also through the production processes, fertilizers,light quality, light intensity, and crop quality.

To effectively control the climate, irrigation, nutrition and lightregime of greenhouse crops in order to beneficially modulate and controlgrowth and attributes of crops, sensors as well as models can beincorporated into a feed-forward/feedback component of a lightingsystem. Feed-forward controllers can use lamp light output to providethe necessary input for plant growth and have the capacity to anticipatethe effects of disturbances on the greenhouse climate and in the lightenvironment and take action within precisely set limits. Specific cropmodels, developed for individual crop species, can be based on data fromsensors and used to estimate the benefits of changing growth regimes(e.g., spectral quality of the light source) to influence or modulatethe outcome (e.g., flowering time). To this extent, the data obtained bythe sensors can be combined with model-based algorithms in a lightingsystem to direct specific changes that influence the plant's growthprocesses or attributes.

SUMMARY OF THE INVENTION

This Summary Of The Invention introduces a selection of certain conceptsin a brief form that are further described below in the DetailedDescription Of The Invention. It is not intended to exclusively identifykey features or essential features of the claimed subject matter setforth in the Claims, nor is it intended as an aid in determining thescope of the claimed subject matter.

Aspects of the present invention are directed to a lighting system thatincorporates optimal irradiation settings to irradiate a surface of thelight sensitive object under a variety of environmental conditions withvarious radiation sources, light sensors to detect light intensity atthe surface, and a controller that controls the power of the radiationsources irradiating the surface of the object according to feedback fromthe sensors. In this manner, the irradiation of the surface can beoptimized to attain desired characteristics such as a predeterminedlight intensity distribution pattern that is formed over the surface ofthe object.

Various radiation sources can be used to irradiate the light sensitiveobject. In one embodiment, an array of ultraviolet radiation sources canbe used to irradiate a surface of the object with ultraviolet radiationhaving a wavelength range that includes ultraviolet-A (UV-A) radiationand ultraviolet-B (UV-B) radiation. In another embodiment, a set ofvisible light sources can irradiate the surface of the object withvisible radiation in conjunction with the ultraviolet radiation sources.In still another embodiment, an infrared source can irradiate thesurface of the object with infrared radiation in addition to theultraviolet radiation sources and the visible radiation sources.

Many different configurations of radiation sources are possible for anembodiment that uses an array of ultraviolet radiation sources with aset of visible light sources and an infrared source. For example, thearray of ultraviolet radiation sources can include a UV-A sourceoperating at a peak wavelength of 365 nm with a full width half maxranging from 5 nm to 10 nm, and a UV-B source operating in a wavelengthrange of 280 nm to 300 nm. The set of visible light sources and infraredsource can include a dark blue light source operating in a wavelengthrange of 440 nm to 450 nm; a blue light source operating at a peakwavelength of 470 nm with a full width half max ranging from 5 nm to 10nm; a green light source operating in a wavelength range of 525 nm to540 nm; a red light source operating in a wavelength range of 620 nm to640 nm; and an infrared source operating in a wavelength range of 725 nmto 740 nm.

A set of light sensors can measure the light intensity at the surface ofthe object. In one embodiment, each light sensor can measure lightintensity in a wavelength range that corresponds to a predeterminedwavelength range emitted from one of the sources that irradiates theobject. The light sensors can include, but are not limited to,photodetectors, photodiodes, and visible light cameras.

A controller can control the power of the radiation sources irradiatingthe surface of the object according to feedback data received from thelight sensors. In this manner, the controller can control the lightintensity over the surface of the object as a function of lightintensity measurements obtained from the light sensors. In oneembodiment, the controller can use the light intensity measurements todetermine whether each source is illuminating the surface of the objectat a dose that delivers the radiation at an intensity that is within anacceptable variation of a predetermined intensity value targeted for thesurface. The controller can adjust the power of each source in responseto determining that the source is illuminating the surface with anintensity that has an unacceptable variation with the predeterminedintensity value targeted for the surface. In this manner, the controllercan adjust the power of the sources to attain a predetermined lightintensity distribution over the surface. The predetermined intensitydistribution can include a variety of different patterns. For example,the predetermined intensity distribution can include individual peaks ofintensity with each corresponding to one of the sources irradiating thesurface. In one embodiment, the predetermined intensity distribution caninclude a set of points along the surface that have a minimal differencein intensity between the points. In another embodiment, thepredetermined intensity distribution can include regions located alongthe surface with varying patterns, types of radiation, wavelengths,dosages, and/or intensities. For example, outer regions of the surfacecan have higher light intensities than the intensities at a centralregion of the surface.

In one embodiment, fluorescent sources can be used to irradiate thesurface of the object in conjunction with any other radiation sourcesthat are used to irradiate the object. Fluorescent sensors can be usedto detect fluorescent radiation reflected from the surface of theobject. In one embodiment, the fluorescent sources and the fluorescentsensors can operate in a pulsed regime to differentiate from fluorescentsignals reflected from the surface that arise from the irradiation bythe other radiation sources.

Light reflectance sensors also can be used to detect radiation reflectedfrom the surface of the object, including fluorescent and/or infraredradiation. In one embodiment, the light reflectance sensors can detectreflected radiation that has time dependent characteristics such asradiation that is generated from sources operating in a pulsed regime.In this manner, the light reflectance sensors can measure a phase-shiftand/or a wavelength-shift of the reflected radiation from the surface.

A first aspect of the invention provides a lighting system, comprising:an array of ultraviolet radiation sources configured to irradiate asurface of a light sensitive surface object with ultraviolet radiationhaving a wavelength range that includes ultraviolet-A (UV-A) radiationand ultraviolet-B (UV-B) radiation, wherein each of the ultravioletradiation sources operates in a predetermined wavelength range thatincludes at least one of: a UV-A radiation wavelength range or a UV-Bradiation wavelength range, wherein at least one of the ultravioletradiation sources operates at a peak wavelength that is within the UV-Bwavelength range; a plurality of light sensors configured to measurelight intensity at the surface of the object, wherein each light sensormeasures light intensity in a wavelength range that corresponds to thepredetermined wavelength range emitted from at least one of theultraviolet radiation sources in the array; and a controller configuredto control the light intensity over the surface of the object byadjusting operational power of the ultraviolet radiation sources as afunction of light intensity measurements obtained by the light sensors,wherein the controller uses the light intensity measurements todetermine whether each ultraviolet radiation source is illuminating thesurface of the object with an intensity that has a variation that ismore than 50% of a predetermined intensity value targeted for thesurface, the controller adjusting the power of an ultraviolet radiationsource in response to determining that the ultraviolet radiation sourceis illuminating the surface of the object with an intensity that has avariation that is more than 50% of the predetermined intensity valuetargeted for the surface, the controller adjusting the power of theultraviolet radiation source as a function of the variation between thelight intensity generated from the source and the predeterminedintensity value targeted for the surface.

A second aspect of the invention provides a lighting system, comprising:an array of ultraviolet radiation sources configured to irradiate asurface of a light sensitive object with ultraviolet radiation having awavelength range that includes ultraviolet-A (UV-A) radiation andultraviolet-B (UV-B) radiation, wherein each of the ultravioletradiation sources irradiates the surface of the object with ultravioletradiation over a predetermined wavelength range, and at least one of theultraviolet radiation sources operates at a peak wavelength that iswithin a UV-B wavelength range; a plurality of light sensors configuredto measure light intensity at the surface of the object, wherein eachlight sensor measures light intensity in a wavelength range thatcorresponds to the predetermined wavelength range emitted from at leastone of the ultraviolet radiation sources in the array; and a controllerconfigured to control the light intensity over the surface of the objectas a function of light intensity measurements obtained from the lightsensors, wherein the controller uses the light intensity measurements todetermine whether each ultraviolet radiation source is illuminating thesurface of the object at a dose that delivers the ultraviolet radiationat an intensity that is within a predetermined acceptable variation witha maximum intensity value targeted for the surface, the controlleradjusting the power of each ultraviolet radiation source in response todetermining that the ultraviolet radiation source is illuminating thesurface with an intensity that has an unacceptable variation with themaximum intensity value targeted for the surface, each ultravioletradiation source that is adjusted in power delivers an adjusted dose ofthe ultraviolet radiation that is a function of an amount of thevariation with the maximum intensity value that is unacceptable.

A third aspect of the invention provides a system for irradiating aplant, comprising: a set of visible light sources configured toirradiate the plant with visible radiation having a range of visiblewavelengths; a set of infrared radiation sources configured to irradiatethe plant with infrared radiation having a range of infraredwavelengths; a set of ultraviolet radiation sources configured toirradiate the plant with ultraviolet radiation having a range ofultraviolet wavelengths; a plurality of light sensors configured tomeasure light intensity at a surface of the plant, wherein each lightsensor measures light intensity in a wavelength range that correspondsto the range of wavelengths emitted from at least one of the sets ofvisible light sources, infrared sources, or ultraviolet radiationsources; and a controller configured to control the irradiation of theplant by the sets of visible light sources, infrared radiation sources,and ultraviolet radiation sources, the controller directing the sets ofvisible light sources, infrared radiation sources and ultravioletradiation sources to provide a predetermined distribution of lightintensity over the plant, the controller adjusting the power of theradiation sources and a direction that the radiation from the radiationsources irradiates the plant as a function of light intensitymeasurements obtained from the light sensors to maintain thepredetermined uniform distribution of light intensity over the plant.

The illustrative aspects of the invention are designed to solve one ormore of the problems herein described and/or one or more other problemsnot discussed.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the disclosure will be more readilyunderstood from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings that depict various aspects of the invention.

FIG. 1 shows a schematic of a lighting system for irradiating a surfaceof a light sensitive object at a predetermined light intensitydistribution according to an embodiment.

FIG. 2 shows a set of elongated structures each having radiation sourcesthat can be deployed in a lighting system for irradiating a surface of alight sensitive object with a predetermined light intensity distributionaccording to an embodiment.

FIG. 3 shows a more detailed view of one of the elongated structuresdepicted in FIG. 2 with its radiation sources in operation according toan embodiment.

FIG. 4 shows examples of light intensity distributions that are obtainedwith one of the elongated structures depicted in FIG. 2 over differentdistances from an area irradiated by the structures according to anembodiment.

FIGS. 5A-5B show measured light intensity distributions obtained from alighting system described herein according to embodiments.

FIGS. 6A-6B show an array of radiation sources including ultravioletradiation sources and visible light sources that can be deployed in alighting system for irradiating a surface of a light sensitive objectwith a predetermined light intensity distribution according to anembodiment.

FIG. 7 shows an example of a spectral power density obtained from alighting system described herein that has the capability to controllight intensity at a surface of an object according to an embodiment.

FIG. 8 shows another example of a spectral power density obtained from alighting system described herein that has the capability to controllight intensity at a surface of an object according to an embodiment.

FIGS. 9A-9B show a schematic of a lighting system for irradiating asurface of a light sensitive object such as a plant at a predeterminedlight intensity distribution that can facilitate uniform distributionthroughout the canopy of the plant according to an embodiment.

FIGS. 10A and 10B show an illustrative operation scenario in whichmultiple sets of ultraviolet radiation sources are operated as afunction of time according to an embodiment.

FIG. 11 shows a block diagram illustrating operating configurations fora lighting system with ultraviolet radiation sources that can irradiatefood items in a food storage container according to an embodiment.

FIG. 12 shows an illustrative lighting system including ultravioletradiation sources and other sources that can irradiate food items in afood storage container according to an embodiment.

FIGS. 13A-13C show examples of various types of food storage containersin which a lighting system with ultraviolet radiation sources can bedeployed to irradiate food items in the containers according toembodiments.

FIG. 14 shows a food storage container in which ultraviolet radiationsources are positioned at various locations in the storage containeraccording to an embodiment.

FIGS. 15A and 15B show illustrative cylindrical-shaped food storagecontainers that can deploy a lighting system with ultraviolet radiationsources to irradiate food items stored in the containers according toembodiments.

FIG. 16 shows an illustrative food storage container with a plurality ofsub-compartments that can deploy a lighting system with ultravioletradiation sources to irradiate food items in the container according toan embodiment.

FIG. 17 shows a schematic block diagram representative of an overallprocessing architecture of a lighting system for irradiating a lightsensitive object according to an embodiment.

It is noted that the drawings may not be to scale. The drawings areintended to depict only typical aspects of the invention, and thereforeshould not be considered as limiting the scope of the invention. In thedrawings, like numbering represents like elements between the drawings.

DETAILED DESCRIPTION OF THE INVENTION

As indicated above, aspects of the present invention are directed to alighting system that incorporates optimal irradiation settings toirradiate a surface of the light sensitive object under a variety ofenvironmental conditions with various radiation sources, light sensorsto detect light intensity at the surface, and a controller that controlsthe power of the radiation sources irradiating the surface of the objectaccording to feedback from the sensors in order to attain desiredcharacteristics such as a predetermined light intensity distributionpattern over the surface of the object.

In one embodiment, the light sensitive object can include a livingorganism such as a plant. As used herein, a plant can include any one ofa vast number of organisms within the biological kingdom Plantae. Ingeneral, a plant includes species that are considered of limitedmotility and generally manufacture their own food. A non-exhaustive listof plants can include, but are not limited to, vegetables, flowers,trees, forbs, shrubs, grasses, vines, ferns, and mosses. In oneembodiment, various radiation sources can be used to irradiate parts ofthe plant such as leaves, a canopy of leaves, branches, trunks, roots,nodes and buds. Although the description that follows is mainly directedto a plant, various embodiments of the present invention are suitablefor use with any light sensitive object where it is desirable toirradiate a surface of the object to alter chemical and biologicalprocesses internal to the object in order to impart certainphysiological responses. Examples of other light sensitive objects thatare suitable for use with a lighting system that incorporates theconcepts of the various embodiments described herein can include, but isnot limited to, living organisms such as plants, humans and animals, aswell as surfaces having a composition (e.g., coating) that can undergochemical/structural change due to radiation.

Other examples of light sensitive objects that are suitable for use witha lighting system that incorporates any of the teachings of the variousembodiments includes food items that can be subject to microorganisms(e.g., pathogenic and spoilage bacteria) that cause foodborne illnesses,spoilage and decomposition, sprouting (e.g., in potatoes, onions) andripening (e.g., with fruit), and attraction of insects. Application ofradiation using the lighting systems described herein can preventfoodborne illnesses, facilitate food preservation, delay sprouting andripening of certain foods, control insects and increase overall foodsafety by effectively eliminating, destroying or inactivating themicroorganisms. A non-exhaustive listing of food items that couldbenefit from irradiation with the lighting systems described hereininclude fruit, vegetables, meat, poultry, fish, drinks (e.g., juices),breads, cheeses, eggs, etc.

In addition to using the lighting systems of the various embodiments tofacilitate food safety, food preservation and control of insects, thelighting systems can also be used to further food quality by generatinginformation that is indicative of the cooking condition or status of thefood items during their preparation. For example, food items that areprepared using one of a number of different cooking techniques that caninclude, but are not limited to, frying, boiling, grilling, baking,browning, heating, roasting, steaming, sizzling, stewing, and warming,can be irradiated with ultraviolet radiation. To this extent, the fooditems can generate different light responses upon excitation with theultraviolet radiation. The light responses that are generated from thefood items are representative of the extent of the cooking of the items,i.e., the current food cooking condition/status of the food. The lightresponses will vary based on the specific biological substances that arein the food items such as, but not limited to, proteins, fats, andcarbohydrates. In addition to the biological substances in the fooditems, the light responses that are excited upon irradiation with theultraviolet radiation will depend on the particular cooking techniquethat is used to cook the food items. The use of the lighting systems toirradiate food items during its preparation can be used to ensure thatthe food items are properly cooked according to the desired manner. Thefood items that this embodiment has applicability with includes any of awide variety of food items that can be cooked using any of theaforementioned cooking techniques.

The various embodiments for controlling the light intensity of radiationirradiating a light sensitive object with a lighting system describedherein can include a number of components, some of which may not beincluded in embodiments. These components and the functions that eachcan perform are described below in more detail. The components andactions can include any now known or later developed approaches that canfacilitate implementation of the concepts and configurations of thevarious embodiments described herein.

As used herein, controlling the light intensity of radiation whileirradiating a light sensitive object means modifying the intensity oflight at different locations of the irradiated surface(s) of the lightsensitive object. Generally, controlling light exposure of a lightsensitive object entails controlling the intensity of radiation,duration of radiation, the wavelength(s) of radiation, and/or the timeschedule of radiation intensity and wavelength.

Ultraviolet radiation, which can be used interchangeably withultraviolet light, means electromagnetic radiation having a wavelengthranging from approximately 10 nm to approximately 400 nm. Within thisrange, there is ultraviolet-A (UV-A) electromagnetic radiation having awavelength ranging from approximately 315 nm to approximately 400 nm,ultraviolet-B (UV-B) electromagnetic radiation having a wavelengthranging from approximately 280 nm to approximately 315 nm, andultraviolet-C (UV-C) electromagnetic radiation having a wavelengthranging from approximately 100 nm to approximately 280 nm. It isunderstood that a light emitting source configured to operate in aparticular range can emit ultraviolet radiation in an adjacent range.For example, as used herein, a UV-C source can also emit UV-B radiation,e.g., 280 nm to 290 nm. Also, as used herein, blue-UV radiation includesat least a portion of the UV-A electromagnetic radiation as well ashigher wavelength visible light, e.g., visible light having a wavelengthranging from approximately 400 nm to approximately 460 nm (360 nm to 460nm in a more particular embodiment).

Generally, ultraviolet radiation, and in particular, UV-B radiation andUV-C radiation is “germicidal,” i.e., it deactivates the DNA ofbacteria, viruses and other pathogens, and thus, destroys their abilityto multiply and cause disease. This effectively results in sterilizationof the microorganisms. Specifically, UV-B radiation and UV-C radiationcause damage to the nucleic acid of microorganisms by forming covalentbonds between certain adjacent bases in the DNA. The formation of thesebonds prevents the DNA from being “unzipped” for replication, and theorganism is neither able to produce molecules essential for lifeprocess, nor is it able to reproduce. In fact, when an organism isunable to produce these essential molecules or is unable to replicate,it dies. Ultraviolet radiation with a wavelength of approximatelybetween about 250 nm to about 290 nm provides the highest germicidaleffectiveness, while an ultraviolet radiation between about 260 nm toabout 310 nm is sufficient for providing overall germicidaleffectiveness, and ultraviolet radiation between 250 nm to 280 nm is arange for facilitating sterilization and disinfection of a vast amountof objects and fluids that can develop the presence of contaminants andmicroorganisms. While susceptibility to ultraviolet radiation varies,exposure to ultraviolet energy in the above range for about 20 to about34 milliwatt-seconds/cm² is adequate to deactivate approximately 99percent of the pathogens.

Also, ultraviolet radiation, and in particular, UV-B radiation incombination with UV-A radiation or blue-UV radiation is germicidal inthat the radiation eliminates, destroys or inactivates microorganismslike pathogenic and spoilage bacteria that can form on light sensitiveobjects such as food items. To this extent, the use of UV-B radiation incombination with UV-A radiation and/or blue-UV radiation can preventfoodborne illnesses, facilitate food preservation, delay sprouting andripening of certain foods like produce and other agricultural products,control insects, and increase overall food safety by effectivelyeliminating, destroying or inactivating the microorganisms.

As used herein, a material/structure is considered to be “reflective” toultraviolet light of a particular wavelength when the material/structurehas an ultraviolet reflection coefficient of at least 30 percent for theultraviolet light of the particular wavelength. A highly ultravioletreflective material/structure has an ultraviolet reflection coefficientof at least 80 percent. Furthermore, a material/structure/layer isconsidered to be “transparent” to ultraviolet radiation of a particularwavelength when the material/structure/layer allows at least ten percentof radiation having a target wavelength, which is radiated at a normalincidence to an interface of the material/structure/layer to pass therethrough.

The description that follows may use other terminology herein for thepurpose of describing particular embodiments only, and is not intendedto be limiting of the disclosure. For example, unless otherwise noted,the term “set” means one or more (i.e., at least one) and the phrase“any solution” means any now known or later developed solution. Thesingular forms “a,” “an,” and “the” include the plural forms as well,unless the context clearly indicates otherwise. It will be furtherunderstood that the terms “comprises,” “comprising,” “includes,”“including,” “has,” “have,” and “having” when used in thisspecification, specify the presence of stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

In the current description, “uniform” refers to variance of less thanten percent. For example, a distribution of intensity over a surface andintensity over a surface are uniform when the intensity varies over thesurface by less than ten percent. In general, the actual intensity maydeviate from uniform intensity over a surface. The variance (deviation)can be measured as a ratio between a difference in the highest andlowest intensity values and the highest intensity value measured inpercent as observed over the surface of the irradiated object. As usedherein, a setting, value, configuration, and/or the like, is considered“optimal” when it is configured to provide the best result for thecorresponding purpose(s) considering all the parameters and using thegiven system. To this extent, optimal does not mean or imply that theresult is the best achievable in a hypothetical, idealized system or thebest achievable using different considerations and/or parameters. Asused herein, unless otherwise noted, the term “approximately” isinclusive of values within +/−ten percent of the stated value.

Turning to the drawings, FIG. 1 shows a schematic of a lighting system10 for irradiating a surface 12 of a light sensitive object 14 with apredetermined light intensity distribution according to an embodiment.The light sensitive object 14 can include, for example, a surface of aplant, fruit, vegetables or other food items, a film surface sensitiveto irradiation, and/or the like. It is understood, that other objectsthat have surfaces that are sensitive to light are suitable for use inthis embodiment. For example, objects such as human skin, surfacescontaining bacteria or microorganisms, and/or the like, are suitable forirradiation with the lighting system 10.

In one embodiment, the lighting system 10 can include an array 16 ofultraviolet radiation sources 18 configured to irradiate the surface 12of the object 14 with ultraviolet radiation having a wavelength rangethat can include UV-A radiation and UV-B radiation. For example, eachultraviolet radiation source 18 can operate in a predeterminedwavelength range that includes at least one of: a UV-A radiationwavelength range or a UV-B radiation wavelength range. In oneembodiment, at least one of the ultraviolet radiation sources 18 canoperate at a peak wavelength that is within the UV-B wavelength range.

The ultraviolet radiation sources 18 can be arranged to irradiate thesurface 12 of the object 14 in a variety of approaches. For example,each of the ultraviolet radiation sources can irradiate a differentregion (e.g., spot) along the surface 12 of the object 14. In oneembodiment, the ultraviolet radiation sources 18 can irradiate eachregion with relatively uniform radiation. In another embodiment, morethan one ultraviolet radiation source 18 can be used to irradiate asingle region on the object, with each irradiating the common region ata different intensity of radiation. In order to facilitate spotirradiation performed by the ultraviolet radiation sources 18, a set ofreflective optical elements can be used to focus the ultravioletradiation to regions on the surface 12 of the object 14. In oneembodiment, each optical element can be configured to focus ultravioletradiation emitted from one of the ultraviolet radiation sources to arespective region on the object 12. Examples of optical elements thatcan be used in conjunction with the ultraviolet radiation sources 18 caninclude, but are not limited to, a lens and/or a set of lenses.

In one embodiment, the array 16 of ultraviolet radiation sources 18 canbe configured for movement about the object 14 to attain one of a numberof targeted intensity distributions over the surface 12 of the object14. For example, each of the ultraviolet radiation sources 18 can beimplemented to have movement in both translational and directionaldegrees of freedom. In one embodiment, the ultraviolet radiation sources18 can be implemented to have movement in both translational anddirectional degrees of freedom by, for example, sliding on a railingsystem. In an embodiment, the array 16 of ultraviolet radiation sources18 can have rotational degree of freedom and rotate around its centeraround a chosen axis.

In one embodiment, the array 16 of ultraviolet radiation sources 18 canbe configured to have a greater amount of ultraviolet radiation sources(e.g., a higher density of ultraviolet radiation sources) located atside portions of the array in comparison to an amount of ultravioletradiation sources located near a central region of the array. Forexample, the side portions of the array 16 can include at least 10% moreultraviolet radiation sources (e.g., a density of ultraviolet radiationsources at least 10% higher) than the amount of ultraviolet radiationsources 18 located near the central region. In one embodiment, theultraviolet radiation sources 18 located at the side portions of thearray 16 can operate at a higher pulsed frequency than the ultravioletradiation sources located near the central region. In one embodiment,the ultraviolet radiation sources 18 located at the side portions of thearray 16 can operate at a higher power than the ultraviolet radiationsources located near the central region. In addition to irradiating theobject at different peak wavelengths, intensity levels, orientation, orirradiation pattern, the radiation from the ultraviolet radiationsources 18 can also differ by polar distribution and angulardistribution.

The lighting system 10 can further include a set of light sensors 20,each of which is configured to measure light intensity at the surface 12of the object 14. In one embodiment, each light sensor 20 can measurelight intensity in a wavelength range that corresponds to thepredetermined wavelength range emitted from at least one of theultraviolet radiation sources 18 in the array 16. As shown in FIG. 1,the light sensors 20 can be located within and/or interchanged with thearray 16 of ultraviolet radiation sources 18. For example, in oneembodiment, the array 16 can include a 3×5 array with ultravioletradiation sources 18 in locations 1,1; 1,2; 1,4; 1,5; 2,1; 2,3; 2,5;3,1; 3,2; 3,4; and 3,5 of the array; while the light sensors 20 canoccupy locations 1,3; 2,2; 2,4 and 3,3. It is understood, the locationsof the ultraviolet radiation sources 18 and the light sensors 20 in thearray 16, as well as the amount of each are only illustrative of onepossible implementation and are not meant to be limiting. Further, it isunderstood that the light sensors 20 can be configured in the lightingsystem 10 apart from the array 16 of ultraviolet radiation sources 18.For example, the light sensors 20 can be located above, below, and/or tothe side of the array 16.

The lighting system 10 can further include a controller 22 that isconfigured to control the light intensity over the surface 12 of theobject 14. In particular, the controller 22 can control the lightintensity over the surface 12 by adjusting the operational power of theultraviolet radiation sources 18 as a function of the light intensitymeasurements obtained by the light sensors 20. In one embodiment, thecontroller 22 can use the light intensity measurements to determinewhether each ultraviolet radiation source 18 is illuminating the surface12 of the object 14 with an intensity that has a relatively smalldeviation from uniformity. In general, a deviation from uniformity thatis more than 50% is indicative of poor intensity uniformity. In suchcases, the controller 22 can adjust the intensity of one or more of theindividual ultraviolet radiation sources 18 to increase the uniformityof the light intensity.

The controller 22 can adjust the power of each ultraviolet radiationsource 18, via a power component 24 that powers the lighting system 10,in response to determining that the ultraviolet radiation source isilluminating the surface 12 of the object 14 in a manner that does notsatisfy a predetermined objective. In one embodiment, the controller 22can adjust the power of each ultraviolet radiation source 18 in responseto determining that the ultraviolet radiation source is illuminating thesurface of the object with an intensity that has a variation that ismore than 50% of the predetermined intensity value targeted for thesurface. In another embodiment, the controller 22 can adjust the powerof each ultraviolet radiation source 18 in response to determining thatthe ultraviolet radiation source is illuminating the surface of theobject with an overall dose that has a variation that is more than 50%of the predetermined intensity value targeted for the surface. Thecontroller 22 can assess whether any of these predetermined objectivesare being met for each particular wavelength that is used to irradiatethe surface 12 of the object 14. It is understood that eachpredetermined objective can be different for each wavelength of lightused for irradiation of the surface 12. In general, the operation of thelighting system 10 and the fulfillment of the objectives will depend onthe distance to the surface 12 of the object 14 from the system, theoverall operational environment of the system including the presence ofother surfaces capable of altering the overall radiation pattern of thesurface, and the light properties of the surface.

In one embodiment, the controller 22 can adjust the power of eachultraviolet radiation source 18 that is powered by the power component24 as a function of the variation between the light intensity generatedfrom the source and the predetermined intensity value targeted for thesurface. In particular, the resultant intensity from the array ofradiation sources 16 is compared to the target intensity and theintensity of one or more sources 18 can be adjusted according to aradiation model to achieve the target intensity. The radiation model cancomprise a computer ray tracing simulation model, which can beimplemented as a data table that lists intensity distribution for agiven set of intensities of sources 18.

In one embodiment, the controller 22 can adjust the ultravioletradiation sources 18 to achieve other targeted objectives associatedwith the intensity of radiation provided to the surface 12 of the object14. For example, the controller 22 can control the ultraviolet radiationsources 18, via the power component 24, to provide higher intensitydelivered to the outer edges of the surface 12 of the object 14, andlower intensity radiation as compared to the intensity delivered to theouter edges irradiating the central inner portions of the surface.Controlling some of the ultraviolet radiation sources 18 to operate withmore power and others to operate at less power in order to have highintensity radiation at the outer edges of the surface with low intensityradiation at the central portion can result in better uniformity over anarea of the object 14.

In one embodiment, the controller 22 can adjust the ultravioletradiation sources 18 based on the feedback measurements provided by thesensors to achieve a targeted dose objective for each of the ultravioletradiation sources 18 irradiating the surface 12 of the object 14. Forexample, the controller 22 can control the ultraviolet radiation sources18 to operate at different pulsed frequencies. In this case, theultraviolet radiation sources 18 can be operated to repeatedly emitultraviolet radiation for a duration of time followed by a duration oftime during which no radiation is emitted. In one embodiment, thecontroller 22 can instruct some of the ultraviolet radiation sources 18to operate at a higher pulsed frequency and others to operate at a lowerpulsed frequency as compared to the higher pulsed frequency. In oneexample, the controller 22 can control the ultraviolet radiation sources18 configured to irradiate the outer edge of the surface 12 of theobject 14 to operate a higher frequency, and have those sourcesconfigured to irradiate the central portion of the surface operate alower frequency. Operating the ultraviolet radiation sources 18 in thismanner can be beneficial because different pulsed frequencies atdifferent locations results in delivering different radiation doses atdifferent locations. This can be beneficial depending on the applicationof the ultraviolet radiation. For instance, in the case of ultravioletink curing, the edges of the ink region might require a higher dose ofradiation for faster ink curing whereas smaller doses of radiation canbe used within the domain.

In one embodiment, the controller 22 can use the data from the sensors20 to control the light intensity over the surface 12 of the object 14that is provided by the ultraviolet radiation sources 18 to maintain apredetermined intensity distribution. In one example, the predeterminedintensity distribution can include a set of points located along thesurface 12 that have a minimal difference in intensity. As used herein,a minimal difference in intensity means that the intensity is uniform.In particular, the controller 22 can receive light intensitymeasurements from the light sensors 20 that are configured to obtainlight intensity data for that area of the surface 12 that encompassesthe set of points. If the intensity measurements from these lightsensors 20 are not within an acceptable variation, then the controllercan adjust the power output of any of the sources irradiating thatregion to ensure that each is providing an intensity that is acceptable.The controller 22 will continue to monitor the intensity measurementsfrom these sets of points and make adjustments to the sources 18 asneeded. The controller 22 can continue with this monitoring andadjusting until it is time to stop the operation. Having a set of pointslocated along the surface that receive essentially the same intensityensures that the region of the surface 12 of the object 14 that containsthe point will have uniform intensity.

In one embodiment, the ultraviolet radiation sources 18 can comprise anycombination of one or more types of ultraviolet radiation emitters.Examples of an ultraviolet radiation emitter can include, but are notlimited to, high intensity ultraviolet lamps (e.g., high intensitymercury lamps), discharge lamps, ultraviolet LEDs, super luminescentLEDs, laser diodes, light emitting sources, solid state light sources,and/or the like. In one embodiment, the ultraviolet radiation sourcescan include a set of LEDs manufactured with one or more layers ofmaterials selected from the group-III nitride material system (e.g.,Al_(x)In_(y)Ga_(1-X-Y)N, where 0≤x, y≤1, and x+y≤1 and/or alloysthereof). Additionally, the ultraviolet radiation sources 18 cancomprise one or more additional components (e.g., a wave guidingstructure, a component for relocating and/or redirecting ultravioletradiation emitter(s), etc.) to direct and/or deliver the emittedradiation to a particular location/area, in a particular direction, in aparticular pattern, and/or the like. Illustrative wave guidingstructures can include, but are not limited to, a wave guide, aplurality of ultraviolet fibers, each of which terminates at an opening,a diffuser, and/or the like.

The ultraviolet radiation sources 18 can operate over a wide range ofwavelengths that span the ultraviolet radiation spectrum. For example,in one embodiment, the ultraviolet radiation sources 18 can operate witha wavelength that ranges from 250 nm to 360 nm. In general, for adequateoptimization the wavelength range of the ultraviolet radiation sources18 can be selected to be significantly narrower to cover 270 nm to 320nm, and in some cases depending on the optimization target, thewavelength range can extend from 280 nm to 300 nm.

In one embodiment, some of the ultraviolet radiation sources 18 can beconfigured as UV-A sources that emit UV-A electromagnetic radiationhaving a wavelength that ranges from approximately 315 nm toapproximately 400 nm, while other ultraviolet radiation sources 18 canbe configured as UV-B sources that emit UV-B electromagnetic radiationhaving a wavelength that ranges from approximately 280 nm toapproximately 315 nm, and blue-UV sources that emit blue-UVelectromagnetic radiation having a wavelength that ranges fromapproximately 400 nm to approximately 460 nm. To this extent, the UV-Asources, the UV-B sources, and the blue-UV sources can be configured tooperate at peak wavelengths in their corresponding wavelength rangeswhile irradiating food items in order to facilitate food safety, foodpreservation and insect control.

The set of ultraviolet radiation sources 18 can be configured toirradiate a surface of food item(s) with ultraviolet radiation having awavelength range that includes ultraviolet-A (UV-A) radiation,ultraviolet-B (UV-B) radiation and blue-ultraviolet (blue-UV) radiation.In one embodiment, the set of ultraviolet radiation sources 18 caninclude at least one UV-B source operating at a peak wavelength that iswithin a UV-B wavelength range and at least one of a UV-A sourceoperating at a peak wavelength that is within a UV-A wavelength range ora blue-UV source operating at a peak wavelength that is within a blue-UVwavelength. For example, the set of ultraviolet radiation sources 18 caninclude at least one UV-B source operating at a peak wavelength that iswithin a UV-B wavelength range and at least one UV-A source operating ata peak wavelength that is within a UV-A wavelength range. In anotherembodiment, the set of ultraviolet radiation sources 18 can include atleast one UV-B source operating at a peak wavelength that is within aUV-B wavelength range and at least one blue-UV source operating at apeak wavelength that is within a blue-UV wavelength range. In yetanother embodiment, the set of ultraviolet radiation sources 18 caninclude at least one UV-B source operating at a peak wavelength that iswithin a UV-B wavelength range, at least one UV-A source operating at apeak wavelength that is within a UV-A wavelength range, and at least oneblue-UV source operating at a peak wavelength that is within a blue-UVwavelength range.

In one embodiment, the set of ultraviolet radiation sources 18 can beused during the preparation of food items in order to provideinformation that is indicative of the present cooking condition orstatus of the food items. For example, at least one UV-A sourceoperating at a peak wavelength that is within a UV-A wavelength rangecan irradiate the food items during cooking. The irradiation of the fooditems with the UV-A radiation will excite a light response that isindicative of the present cooking status of the items. As notedpreviously, the light response will depend on the specific biologicalsubstances (e.g., proteins, fats, and carbohydrates) that are in thefood items that are being cooked, as well as the particular cookingtechnique that is used to cook the food items. In one embodiment, thelight sensors 20 can detect the light response excited from the fooditems and feedback this information to the controller 22 which candetermine the present food cooking condition/status depending on thelight response information provided by the light sensors 20. Thecontroller 22 via an output component can inform the person cooking thefood as to the condition or status. In this manner, the person cookingthe food can use this information to ensure that the food is cookedaccording to specification. Until the food has reached its desiredcondition, the ultraviolet radiation sources 18, the light sensors 20and the controller 22 can continue to operate in conjunction with oneanother to monitor the cooking of the food items.

In one embodiment, the set of ultraviolet radiation sources 18 can eachoperate at a different peak wavelength (λ). For example, the ultravioletradiation source λ₁₁ at the location 1,1 in the array 16 can operate ata peak wavelength of λ₁, the source λ₁₂ at the location 1,2 can operateat a peak wavelength of λ₂, the source λ₁₄ at the location 1,4 canoperate at a peak wavelength of λ₃, the source λ₁₅ at the location 1,5can operate at a peak wavelength of λ₄, and, so forth. In anotherembodiment, at least one of the sources in the array 16 of ultravioletradiation sources 18 can operate at a wavelength with a peak emission at295 nm with a full width half max ranging from 5 nm to 10 nm. It isunderstood, that these are only few implementations of peak wavelengthsfor the ultraviolet radiation sources 18 and are not meant to belimiting.

The capability of the ultraviolet radiation sources 18 to irradiate thesurface 12 of the object 14 will depend on where the lighting system 10is installed, the distance that the surface 12 of the object 14 is awayfrom the system, an angle at which the radiation impacts the surface,etc. In one embodiment, where the ultraviolet radiation sources 18include ultraviolet LEDs, each of the LEDs can irradiate at least aportion of the surface 12 of the object 14 from distances that rangefrom a few centimeters to a meter. In one embodiment, the ultravioletradiation sources 18 such as the ultraviolet LEDs can be equipped withoptical elements to focus the ultraviolet radiation to a particularportion of the surface 12 of the object 14. Examples of optical elementsthat can be used with the ultraviolet radiation sources 18 can include,but are not limited to, mirrors, lenses, prisms, etc.

The light sensors 20 can include a variety of sensors that can detectlight reflected from the surface 12 of the object 14. For example, thelight sensors 20 can include, but are not limited to, photodetectors,photodiodes, and the like, that can detect light reflected from thesurface 12. In one embodiment, the light sensors 20 can include lightreflectance sensors that can detect radiation reflected from the surface12 of the object 14 including fluorescent and infrared radiation. In oneembodiment, the light reflectance sensors can be used to detectreflected radiation having time dependent characteristics that isgenerated from ultraviolet radiation sources 18 operating in a pulsedregime. In this manner, the light reflectance sensors can measure aphase-shift and a wavelength-shift of the reflected radiation from thesurface 12. The light sensors 20 can also include light intensitysensors that can detect the intensity of the radiation at the surface 12of the object 14. In another embodiment, the light sensors 20 caninclude fluorescent sensors to detect fluorescent radiation reflectedfrom the surface 12 of the object 14. The light sensors 20 can includeinfrared sensors to detect infrared radiation reflected from the surface12 of the object 14. In still another embodiment, the light sensors 20can include at least one visible camera to acquire image datecorresponding to the visible fluorescent radiation from the surface ofthe object 14.

The controller 22 can include various components to facilitate theoperation of the lighting system 10 including the aspect of controllingthe irradiation of the surface 12 of the object 14 with the array 16 ofultraviolet radiation sources 18, including controlling the wavelength,the intensity, the dosage and frequency of the radiation, based onfeedback from the light sensors 20. For example, the controller 22 caninclude a timer with switches and/or the like, to manage the durationthat the ultraviolet radiation sources 18 are on for a particularapplication. To this extent, use of the timer can ensure that radiationincluding spot irradiation is applied to the surface of the object 12for that duration (e.g., a dosage timer). This includes scenarios wherethe ultraviolet radiation sources 18 operate in a pulsed regime. In oneembodiment, each of the ultraviolet radiation sources 18 in the array 16can deliver ultraviolet radiation to the surface 12 of the object 14 inshort pulses. For example, the duration of the short pulses can includepulses of a duration and/or separated by a duration on the order of amillisecond.

The time between pulses can be selected to allow the array 16 ofultraviolet radiation sources 18 to cool a desired amount beforeemitting the next pulse. In one embodiment, each pulse of ultravioletradiation generated from an ultraviolet radiation source 18 can be lessthan an amount of time needed for achieving a steady state temperatureof operating the ultraviolet radiation source. This facilitatesoperation of the ultraviolet light emitting devices at a sufficientlylow temperature for reliable operation. As described herein, each pulseof ultraviolet radiation generated from an ultraviolet radiation source18 can be followed by a pause to reduce the temperature of theultraviolet radiation source. In one embodiment, the pauses in pulses ineach of the ultraviolet radiation sources 18 can reduce a temperature ofthe array 16 to a level that differs from an ambient temperature by atmost 50%. In another embodiment, the pauses in pulses in each of theultraviolet radiation sources 18 can reduce the temperature of the arrayto a level that differs from the ambient temperature by at most 20%.

In an embodiment in which the object 14 is a plant and the lightingsystem 10 is used to facilitate the growth of the plant, the timer canbe used to coordinate the active operation of the radiation sources tocorrespond with the amount of daylight in a particular day, andinactivate the sources during nighttime hours. For example, the array 16of ultraviolet radiation sources 18 can be scheduled to irradiate thesurface 12 of the object 14 for a predetermined duration that is no morethan six hours per day. For example, the timer can be used facilitate anillumination of the object 14 over a period of several days. In thismanner, the controller 22 can detect any changes that occur on theirradiated surface (e.g., changes in size and color of the surface aswell as changes in fluorescence of the surface) and store such resultsfor future analysis. In one embodiment, the controller 20 operating inconjunction with the timer can manage the amount of time that theultraviolet radiation sources 18 radiate in the UV-A range versus theUV-B range. The duration and frequency treatment that the ultravioletradiation sources 18 are utilized can depend on detected conditionsignals provided to the controller 22 by any of the sensors 20.

The controller 22 can also be used to turn off the ultraviolet radiationsources 18 upon any detected conditions provided by any of the lightsensors 20. For example, the controller 22 can be configured tointerrupt the operation of the ultraviolet radiation sources 18 inresponse to receiving light intensity signals from the light sensors 20and determining that the light intensity at the surface 12 of the object14 has exceeded an acceptable variation with a predetermined intensityvalue targeted for the surface. For example, in one embodiment, if thecontroller 22 determines that any of the ultraviolet radiation sources18 is illuminating the surface of the object at a dose that delivers theultraviolet radiation at an intensity that has exceeded an acceptablevariation with the predetermined intensity value that is at most 5%,then controller 22 can instruct the power component 24 to power off thesources.

In an embodiment in which the object 14 is a food item and the lightingsystem 10 is used to facilitate food safety, food preservation, foodquality, and/or control insect infestation, the controller 22 along withthe sensors 20 can be used to control the operation of the ultravioletradiation sources 18 and the light intensity of the radiation thatirradiates the food. For example, the controller 22 can control thelight intensity over the surface of a food item as a function of lightintensity measurements obtained from the light sensors 20. In oneembodiment, the controller 22 can maintain the light intensity at apredetermined light intensity value that enhances or prolongs thelongevity or shelf life of food items, while eliminating the formationof microorganisms including bacteria, viruses, and other potentialpathogens on the food. In particular, the controller 22 can use thelight intensity measurements to determine whether each ultravioletradiation source 18 is illuminating the surface of the food at a dosethat delivers the ultraviolet radiation at an intensity that is withinan acceptable variation with the predetermined light intensity value.The controller 22 can then adjust the power of an ultraviolet radiationsource 18 in response to determining that the ultraviolet radiationsource is illuminating the surface with an intensity that has anunacceptable variation with the predetermined light intensity valuetargeted for the surface. In this manner, each ultraviolet radiationsource 18 that is adjusted in power delivers an adjusted dose of theultraviolet radiation that is a function of an amount of theunacceptable variation with the predetermined light intensity value.

A timer that is integrated with the controller 22 or a separatecomponent can be used to coordinate the irradiation of the food itemswith the ultraviolet radiation sources 18. The schedule in which theultraviolet radiation sources 18 operate will depend on the type of foodto be irradiated, the location of the food (e.g., a refrigerator, acounter, a food storage unit, a food production or processing facility,etc.), the time of day, the temperature in which the food is stored orprocessed, the time of year (e.g., summer, winter, spring, fall). It isnoted that the lighting systems described herein can be implemented tooperate in a variety of locations including, but not limited to arefrigerator, a food storage container, a kitchen countertop, a foodmanufacturing or processing facility, etc. In an embodiment in which thelighting system 10 is implemented in a refrigerator, the ultravioletradiation sources 18 can be configured to irradiate all or specific fooditems in the refrigerator for up to six hours per day over a period ofseveral days. As noted before, the duration and frequency that theultraviolet radiation sources 18 are utilized can depend on detectedconditions (e.g., changes in size and color of the surface on the fooditems) provided to the controller 22 by any of the sensors. Also, thecontroller 22 can store the detected conditions as data for futureanalysis and as a reference for selecting the settings of theultraviolet radiation sources 18 for irradiating similar food items. Forexample, in one embodiment, the controller 22 can include a memorystorage capable of recording the various data obtained from the lightsensors 20. To this extent, the controller 22 can retrieve the data forfurther analysis and optimization of the irradiation settings.

In one embodiment, the controller 22 can also include a wirelesstransmitter and receiver that is configured to communicate with a remotelocation via Wi-Fi, BLUETOOTH, and/or the like. As used herein, a remotelocation is a location that is apart from the lighting system 10. Forexample, a remote computer can be used to transmit operationalinstructions to the wireless transmitter and receiver. The operationalinstructions can be used to program functions performed and managed bythe controller 22. In another embodiment, the wireless transmitter andreceiver can transmit data calculations (e.g., changes), and data fromthe sensors to the remote computer.

In one embodiment, the controller 22 can include an input component andan output component to allow a user to interact with the lighting system10 and to receive information regarding the surface 12 of the object 14and the treatment thereto with the ultraviolet radiation sources 18. Inone embodiment, the input component can permit a user to select one oftwo modes of operating the lighting system 10. For example, the twomodes of operation can include a surface disinfection mode and a plantgrowth promotion mode. In another example directed to the irradiation offood items, there can be a food safety mode, a food preservation modeand an insect control mode. Each of these modes for the various examplescan be characterized by its power spectral density and intensity ofirradiation. In one embodiment, the input component can permit a user toadjust at least one of the aforementioned plurality of operatingparameters. This can include making adjustments during the operation ofthe ultraviolet radiation sources 18 and/or prior to initiating atreatment. In one embodiment, the input component can include a set ofbuttons and/or a touch screen to enable a user to specify various inputselections regarding the operating parameters. In one embodiment, theoutput component can include a visual display for providing statusinformation on the irradiation of the object (e.g., time remaining,light intensity), status information of the object (e.g., changes inshape and size), a simple visual indicator that displays whetherirradiation is underway (e.g., an illuminated light), or if theirradiation is over (e.g., absence of an illuminated light).

The controller 22 can be configured to operate within the lightingsystem 10 in one of a number of implementations. For example, as shownin FIG. 1, the controller 22 can be implemented as a centralizedon-board control unit for the ultraviolet radiation sources 18 and thelight sensors 20. In another embodiment, the controller 22 can bedistributed throughout the lighting system 10. For example, thecontroller 22 can be distributed with the various components of thelighting system 10, such that a portion of the controller is implementedwith the array of ultraviolet radiation sources 18 and light sensors 20.In another embodiment, the controller can be implemented with eachindividual source and sensor to perform individual control of thatparticular component or groups of components.

In addition to powering the ultraviolet radiation sources 18, the powercomponent 24 is configured to provide power to the light sensors 20, thecontroller and any other components that can be used with the lightingsystem 10. In one embodiment, the power component 24 can take the formof one or more batteries, a vibration power generator that can generatepower based on magnetic inducted oscillations or stresses developed on apiezoelectric crystal, and/or the like. In another embodiment, the powercomponent 24 can include a super capacitor that is rechargeable. Otherelements that are suitable for use as the power component 24 can includea mechanical energy to electrical energy converter such as apiezoelectric crystal, and a rechargeable device.

The aforementioned components of the lighting system 10 are onlyillustrative of one possible configuration. It is understood that thelighting system 10 can utilize other components in addition to, or inplace of those described herein. These additional components can performsimilar functions to those described herein, different ones, orfunctions that complement the operation of the ultraviolet radiationsources 18, the light sensors 20 and the controller 22. The type ofadditional components and functionalities that are performed will dependon the type of light sensitive object that is to be irradiated and theresult that is desired through irradiation by the sources.

In one embodiment, the array 16 can include a set of visible lightsources, interspersed with the ultraviolet radiation sources 18 and thelight sensors 20, to irradiate the surface 12 of the object 14 withvisible radiation. The set of visible light sources can irradiate thesurface 12 of the object 14 in conjunction with the ultravioletradiation sources 18. In one embodiment, the set of visible lightsources can include at least one blue light source and at least one redlight source. It is understood that the visible light sources can beimplemented apart from the ultraviolet radiation sources 18. Examples ofvisible light sources can include, but are not limited to, lightemitting diodes, fluorescent lighting, incandescent lighting, and/or thelike. In one embodiment, the visible light sources can include a set oflight emitting diodes (LEDs) operating in a blue, green, and red range.The visible set of LEDs in the array can be operated to provide asufficient intensity of light to allow for plant growth.

In one embodiment, the array 16 can include a set of infrared sources,interspersed with the ultraviolet radiation sources 18 and the lightsensors 20, as well as the visible light sources, to irradiate thesurface 12 of the object 14 with infrared radiation. Examples ofinfrared sources can include, but are not limited to, light emittingdiodes, incandescent sources, and/or the like. It is understood that theinfrared sources can be implemented outside of the array 16 of theultraviolet radiation sources 18 and the light sensors 20.

The sets of visible light sources and infrared sources can each includea variety of sources that operate over a wide range of wavelengths.Generally, the sets of visible light sources and infrared sources canirradiate an entirety of the surface 12 of the object 14 with awavelength that ranges from 430 nm to 800 nm. In one embodiment, the setof visible light sources can include a dark blue visible light sourceoperating in a wavelength ranging from 440 nm to 450 nm, a blue visiblelight source operating at a peak wavelength of 470 nm and a full widthhalf max ranging from 5 nm to 10 nm, a green visible light sourceoperating in a wavelength ranging from 525 nm to 540 nm, a red visiblelight source operating in a wavelength ranging from 620 nm to 640 nm, ared visible light source operating at a peak wavelength of 660 nm and afull width half max ranging from 5 nm to 10 nm, while the set ofinfrared sources can operate in a wavelength ranging from 725 nm to 740nm. In this embodiment, the array 16 of ultraviolet radiation sources 18can include a UV-A source operating at a peak wavelength of 365 nm witha full width half max ranging from 5 nm to 10 nm, and a UV-B sourceoperating in a wavelength range of 280 nm to 300 nm. It is assumed thatfor these values, the peak wavelength is defined to within 1 nm to 5 nm.

Sets of these visible light sources and infrared sources that areconfigured to operate with the aforementioned wavelengths can bebeneficial when considering, for example, treatments and irradiation ofplants. The visible and infrared light can be beneficial for plantgrowth and plant photosynthesis, while the ultraviolet radiation can bebeneficial for production of flavonoids within a plant. In oneembodiment, the visible light sources can irradiate the surface 12 ofthe light sensitive object 14 with a wavelength that ranges from 430 nmto 560 nm. In another embodiment, the visible light sources canirradiate the surface 12 of the light sensitive object 14 with awavelength that ranges from 600 nm to 800 nm.

In one embodiment, where the object 14 is a plant, the sets of visiblelight sources and infrared sources can be configured to irradiate theplant according to a schedule that follows the amount of daylight anddarkness in a given day of a year for a given location. That is, the setof visible light sources and infrared sources can be operational toirradiate the plant during daylight hours and inoperative duringnighttime hours. For example, LEDs operating in a blue, a green, and ared range can be operated to provide a sufficient intensity of light toallow for plant growth, while an infrared set of LEDs can be operated toprovide control over the temperature environment of the plant.

In another embodiment where the object 14 is a plant, the ultravioletradiation sources, the visible light sources, and the infrared sourcescan be implemented as a grow lamp fixture with adjustable intensitiesthat are configured to operate in various modes. For example, the growlamp fixture can include a dark blue source that is approximately 10% ofintensity of the grow lamp fixture; a blue source that is approximately5% of the intensity of the grow lamp fixture; a green source that isapproximately 5% of the intensity of the grow lamp fixture; a red sourcethat is approximately 20% of intensity of the grow lamp fixture; a red660 source that is approximately 50% of the intensity of the grow lampfixture; an infrared source that is 5% of the grow lamp fixture; a UV-Asource that is approximately 5% of the intensity of the grow lampfixture; and a UV-B source that is approximately 5% of the intensity ofthe grow lamp fixture. The chosen percentages can be based on thecurrent state of the art research and experimentation for optimal growthof different type of plants. In particular, such a combination iscurrently understood to be advantageous for growth of Cannabaceae familyof plants. It is understood that some derivation from above schedule isallowable. In particular a deviation of about 50% of the stated percentvalues can be utilized.

It is understood that the lighting system 10 can include other radiationsources in addition to, or in place of, the set of visible light sourcesand infrared sources. For example, fluorescent lights, high pressuresodium lights, metal halide lamps, and any other high intensitydischarge lamps that are typically employed for growth of plants can beused with, or in place of the set of visible light sources and infraredsources. In one embodiment, the lighting system 10 can include a set offluorescent sources to irradiate the surface 12 of the object 14 inconjunction with the ultraviolet radiation sources 18, and a set offluorescent sensors to detect fluorescent radiation reflected from thesurface 12 of the object 14.

In one embodiment, the fluorescent radiation sources and the fluorescentsensors can operate in a pulsed regime to differentiate from thefluorescent signals reflected from the surface that arise from theirradiation by the ultraviolet radiation sources 18. Alternatively, thesources of fluorescent signals can be filtered by wavelength to resultin a clear collection of fluorescent signals from the surface 12 of thelight sensitive object 14. It is understood that any timing fordelivering the radiation to the light sensitive surface and collectingthe fluorescent signal from the surface is possible. In an embodiment, atime resolved fluorescence can be employed, wherein the fluorescentradiation source can operate in a pulsed regime and the fluorescent datacan be collected as the fluorescent signal is decaying. This method isknown also as a transient fluorescent response as it allows fordetermining the lifetime of fluorescence, and possibly a phase delaybetween a harmonic excitation and a response which can lead to aparticular sensing signature for the light sensitive surface 12.

In one embodiment, a set of test radiation sources can be utilized forperforming one of a variety of analyses relating to the irradiation ofthe object 14. The set of test sources can include, but are not limitedto, light emitting diodes, Xeon lamp source, a mercury lamp, etc. In oneembodiment, the set of test sources can be used to induce fluorescentsignals from the surface 12 of the object 14, while a set of fluorescentsensors can be used to detect the signals and provide them to thecontroller 22. In one embodiment, the test sources can includefluorescent sources such as ultraviolet radiation sources operating in apulsed mode at peak wavelengths. The peak wavelengths of the testsources can be different from the peak wavelengths of the ultravioletradiation sources 18 that are also used to irradiate the surface 12 ofthe object 14.

The controller 22 can receive the fluorescent signals from thefluorescent sensors as well any other sensors that are collecting datarelating to the irradiation of the surface 12 of the object 14 by thesources. In one embodiment, the controller 22 can perform an analysis onthe measurements to determine the presence of flavonoids within theplant, to attest the chemical content of the surface material base onfluorescence data, and/or the like. Generally, the analysis can includeirradiating the object surface with ultraviolet light, receiving thefluorescence light data, and comparing the fluorescence light data withexisting tabulated values to attest the properties of the materialcomprising the surface of the object. It is understood that the analysiscan be performed as the controller 22 receives the fluorescent signals,or the analysis can be performed after all of the signals have beenreceived and recorded in a storage (memory, database, etc.).

In one embodiment, other types of ultraviolet radiation sources can beused in addition to the UV-A, UV-B radiation sources and blue-UVradiation sources. For example, UV-C radiation sources can be used todisinfect the surface 12 of the object 14 and remove bacterial or fungicontamination therefrom. In one embodiment, solid stave UV-C radiationsources operating in the wavelength range of 260 nm to 280 nm can beused for disinfection and removal of contaminants from the surface.

The lighting system 10 can further include additional sensors that canmeasure a plurality of conditions associated with irradiating the lightsensitive object 14. In an embodiment in which the light sensitiveobject 12 is a plant and the application of the lighting system 10 is tofacilitate growth of the plant, the additional sensors can include a setof environmental condition sensors that detect conditions of theenvironment in which the plant is located during irradiation by theultraviolet radiation sources 18 and any other sources such as visiblelight sources and infrared sources. In one embodiment, the environmentalcondition sensors can include a temperature sensor, a humidity sensor, aCO₂ sensor, a water sensor, and a nutrient sensor. For example, atemperature sensor can measure the temperature surrounding the plant,the humidity sensor can measure the humidity surrounding the plant, theCO₂ sensor can measure the CO₂ levels surrounding the plant, a watersensor can measure an amount of water surrounding the plant or on theleaves, branches, etc., while the nutrient sensor can measure thepresence of various nutrients (e.g., nitrogen (N), phosphorus (P),potassium (K), calcium (Ca), sulfur (S), magnesium (Mg), sodium (Na),etc.) in the plant. These environmental condition sensors are onlyillustrative of a few possibilities, and it is understood that othersensors can be used to obtain environmental conditions related to thegrowth of a plant or plants in a controlled environment such asgreenhouses, warehouses, etc. For example, an air pressure sensor canmeasure the air pressure of the location in which the plant is located,and an air movement sensor can measure the air speed in close proximityto the plant.

The lighting system 10 can include other sensors in addition to theenvironmental condition sensors. For example, the lighting system 10 caninclude sensors that measure operational data associated with theirradiation by the ultraviolet radiation sources and any other sources.Other examples of sensors that can be used in the lighting system 10 caninclude, but are not limited to, chemical sensors, temperature sensors,humidity sensors, and/or the like. Those skilled in the art willappreciate that the type and amount of sensors used with the lightingsystem 10 can vary, and will depend on what the light sensitive object14 comprises and the application or reason for irradiating the object.

Also, it is understood that the environmental condition sensors andother operational sensors can be used in embodiments in which thelighting systems described herein are used to irradiate food items tofacilitate food safety, food preservation, food quality, insect control.For example, a temperature sensor can measure the temperaturesurrounding the food items, the humidity sensor can measure the humiditysurrounding the food items, the CO₂ sensor can measure the CO₂ levelssurrounding the food items, a water sensor can measure an amount ofwater surrounding food items (e.g., water content in fruits, vegetables,etc.), while a nutrient sensor can measure the presence of variousnutrients (e.g., nitrogen (N), phosphorus (P), potassium (K), calcium(Ca), sulfur (S), magnesium (Mg), sodium (Na), etc.) that are presentand discernible in the food items.

In one embodiment, in which the object 14 is a plant, the controller 22can control the irradiation by the ultraviolet radiation sources 18 andany other sources including, but not limited to, the visible lightsources, the infrared sources and the fluorescent sources according to apredetermined optimal irradiation settings specified for variousenvironmental conditions in which the plant is located. The controller22 can adjust the irradiation settings of the sources as a function ofthe measurements obtained by the light sensors 20 as well as any of theother types sensors mentioned above. That is, the controller 22 can usethe measurement data from the sensors as feedback to adjust the power ofthe sources and the settings of the sources such as, but not limited to,wavelength, dosage, intensity, frequency, in order to facilitate growthand impart change to the plant. In one embodiment, the controller 22 canuse the data feedback from the sensors to detect changes in the plantthat include, but are not limited to, size, shape, color, temperatureand overall harvest yield. In this manner, the controller 22 can controlthe radiation sources to operate at a target wavelength and intensitywith an intensity distribution pattern for a duration that is designedto attain a certain effect in the plant (e.g., increase production of acertain flavonoid and/or antioxidants). It is understood that, thecontroller 22 can use feedback of measurements from the sensors 20 toadjust any combination of various aspects of the irradiation of theplant such as wavelength, intensity, duration, and/or the like, of theirradiation.

In embodiments in which the object 14 includes food items, thecontroller 22 can control the irradiation by the ultraviolet radiationsources 18 (e.g., UV-A sources, UV-B sources, UV-C sources, and blue-UVsources) and any other sources including, but not limited to,fluorescent sources according to a predetermined optimal irradiationsettings specified for various environmental conditions in which thefood may be located. For example, the controller 22 can adjust theirradiation settings of the sources as a function of the measurementsobtained by the light sensors 20 as well as any of the other typesabove-mentioned sensors that are deployed. That is, the controller 22can use the measurement data from the sensors as feedback to adjust thepower of the sources and the settings of the sources such as, but notlimited to, wavelength, dosage, intensity, frequency, in order tofacilitate food safety, food preservation including prolonging thelongevity or shelf-life of the food during storage, processing, and/orshipping, and insect control. In one embodiment, the controller 22 canuse the data feedback from the sensors to detect changes in the fooditems that include, but are not limited to, size, shape, color,temperature and smell. In this manner, the controller 22 can control theradiation sources to operate at a target wavelength and intensity withan intensity distribution pattern for a duration that is designed toattain a certain effect on the food.

In embodiments in which the object 12 is a living organism such as aperson or an animal, the lighting system 10 can be used to apply amedical treatment, the environmental conditions can include variousvital signs such as, for example, blood pressure, heart rate,temperature, pulse, humidity of the skin, and reflectivity of the skin.In this embodiment, sensors can be used to obtain vital signs such as,for example, blood pressure, heart rate, temperature, pulse, humidity ofthe skin, and reflectivity of the skin. In one embodiment, thecontroller 22 can use the data feedback from the sensors that containvital sign data to detect changes in a person or an animal.

FIG. 2 shows a plurality 26 of elongated structures 28, each havingradiation sources 30 that can be deployed in a lighting system forirradiating a surface of a light sensitive object with a predeterminedlight intensity distribution according to an embodiment. The radiationsources 30 in each structure 28 can include, but are not limited to,ultraviolet radiation sources, visible light sources, infrared sources,fluorescent sources and combinations thereof. The radiation sources 30can be powered by a power component 24. In one embodiment, as shown inFIG. 2, a power component 24 can power two elongated structures 28.However, it is understood that the radiation sources 30 of thestructures 28 can be powered with other configurations. For example,each structure 28 can be powered by its own corresponding powercomponent. In another embodiment, a single power component 24 can beused to power all of the radiation sources 30 in the set 26.

Although not shown in FIG. 2, the plurality 26 of elongated structures28 having radiation sources 30 can be implemented in a lighting systemhaving any combination of the components described herein. For example,a controller and light sensors can be deployed with the plurality 26 ofelongated structures 28 having radiation sources 30. In addition,depending on the application of the lighting system with the elongatedstructures, other sensors such as light sensors, fluorescent sensors andany of the environment condition sensors and sensors that measureoperational data associated with the irradiation can be used with theradiation sources 30. In one embodiment, the sensors can be interspersedwith the radiation sources 30 in each of the structures 28.

FIG. 3 shows a more detailed view of one of the elongated structures 28depicted in FIG. 2 with its radiation sources 30 in operation over anarea 32 according to an embodiment.

FIG. 4 shows another view of one of the elongated structures 28 depictedin FIG. 2 with its radiation sources 30 in operation along withillustrative light intensity distributions 36 obtained at variousdistances from an area that is irradiated with the elongated structureaccording to an embodiment. In one example, a light intensitydistribution 36 was obtained from an implementation having a distance of20 centimeters (cm) separating the elongated structure 28 and the areairradiated by the structure. Other light intensity distributions shownin FIG. 4 were obtained at a distance of 30 cm and 40 cm. As shown inFIG. 4, the light intensity distribution over an area irradiated by theradiation sources from the elongated structure 28 is uniform over thevarious distances. In particular, the light intensity distributiongenerated from the elongated structure 28 is not impaired as thedistance between the irradiated area and the sources of the structureincreases from 20 cm to 30 cm and to 40 cm.

FIGS. 5A-5B show measured light intensity distributions obtained from alighting system described herein according to an embodiment. Both of thelight intensity distributions in FIGS. 5A-5B were obtained from alighting system configured with a target objective to control the lightintensity distribution over an area irradiated by the system to have alow variation. As used herein, a low variation in light intensitydistribution means a uniform intensity. In the examples of FIGS. 5A-5B,the lighting system was configured to control the light intensitydistribution over the area irradiated by the system to have a variationof intensity. It is understood that the lighting system could beconfigured to control the light intensity distribution with othervariations.

The light intensity distributions of FIGS. 5A-5B were obtained atvarying distances separating the lighting system and the area irradiatedby the system. In particular, the light intensity distribution of FIG.5A was obtained at an implementation where the lighting system isseparated from the area undergoing irradiation by 30 cm, while the lightintensity distribution of FIG. 5B was obtained at a separation distanceof 50 cm. As shown in FIG. 5A, the light intensity distribution ischaracterized by a colored contour plot with each color corresponding tothe intensity value and reported in W/m². The differences between thelight intensity distributions of FIGS. 5A and 5B are due to a distancebetween the illumination source from the surface. In particular, in FIG.5A the source is positioned 30 cm above the surface, while in FIG. 5Bthe source is positioned 50 cm above the surface.

As noted above, the lighting system of the various embodiments describedherein is well suited for use with irradiating a plant. It is well knownthat ultraviolet radiation can affect various mechanisms of a plant. Forexample, plants use sunlight as an energy source and as an importantenvironmental signal to regulate growth and development. Higher plants,such as the model plant Arabidopsis thaliana (Arabidopsis) use sunlightsignals to regulate a whole range of developmental processes andadaptations including germination, de-etiolation, shade avoidance,stomatal development, circadian rhythm, and flowering. More details ofthe effect that ultraviolet light has on the regulation of growth anddevelopment of a plant including the signaling pathways of ultravioletlight in a plant and their transcriptional responses are described byMuller-Xing et al., “Footprints of the Sun: Memory of UV and LightStress in Plants.” Frontiers in Plant Science, Vol. 5 (September 2014),pp 1-11.

Because ultraviolet light can affect the various functions of plantgrowth and health, it is desirable that the lighting system of thevarious embodiments be flexible in order to adequately administerultraviolet radiation to a plant. As mentioned above, the controller 22is configured to control various parameters of the ultraviolet radiationthat irradiates the plant based on feedback from a multitude of sensorsincluding but not limited to, light sensors and environmental conditionsensors. Examples of some the parameters that can be controlled by thecontroller 22 include, but are not limited to, the wavelength ofultraviolet radiation, the overall dose of ultraviolet radiation to theplant, the intensity of the ultraviolet radiation sources, the durationand frequency of the irradiation. Although different plants respondsignificantly different to ultraviolet radiation, the inventors of thevarious embodiments described herein have found that ultravioletradiation with a peak wavelength at about 295 nm with a full width halfmax range of 5 nm to 20 nm is suitable for plant growth and health,while a peak wavelength at about 295 nm and a narrower full width halfmax range of 10 nm to 20 nm is also beneficial. In one embodiment, adose in the range of 0.1 kJ/m² to 20 kJ/m² is suitable for plant growthand health.

FIGS. 6A-6B show an array 38 of radiation sources 40 includingultraviolet radiation sources and visible light sources that can bedeployed in a lighting system for irradiating a surface of a lightsensitive object (not shown) with a predetermined light intensitydistribution according to an embodiment. In particular, FIG. 6A showsthe array 38 of radiation sources 40 in a non-operational state, whileFIG. 6B shows the array of sources in an operational state. In oneembodiment, the array 38 of radiation sources 40 can include visiblelight sources such as blue light sources, red light sources and whitelight sources and ultraviolet radiation sources. The array of visiblelight sources and ultraviolet radiation sources can be distributedthroughout the array to provide a predetermined pattern of visible lightand ultraviolet radiation to an object. It is understood that thepredetermined pattern will depend on the object that is irradiated bythe sources, the sources that are used in the array and the effect thatis desired from the use of the sources to irradiate the object. Forexample, in a scenario where the object is a plant, blue light sources,red light sources and white light sources can be used to promote plantgrowth, while the ultraviolet radiation sources can be used to affectplant chemistry, such as affect plant flavonoid content.

Although not shown in FIGS. 6A-6B, a controller and a set of any of theaforementioned sensors can be used in conjunction with the array 38 ofradiation sources 40. For example, the controller can be used to controlthe light intensity that is provided to the surface of the object by theradiation sources. In one embodiment, as noted above, the controller canreceive light intensity measurements from the light sensors measuringthe light intensity over the surface of the object, which the controllercan use to determine if the light intensity from each of the sourcesirradiating the object is within an acceptable variation, as well asdetermine if the overall light intensity from all of the sources iswithin another predetermined variation value specified for theirradiation of the object. In one embodiment, the controller can be usedto impart certain effects on the object. In the scenario where theobject is a plant, the controller can use data from any of theaforementioned environment condition sensors to promote plant growth bystimulating flavonoid and an antioxidant production in the plant. Forexample, the controller can used the feedback measurements from thesensors to control the radiation sources to operate according to certainsettings (e.g., dosage, wavelength, intensity, frequency and duration)that have been previously determined to facilitate plant growth andhealth under various growth conditions.

In one embodiment, the array 38 of radiation sources 40 of FIGS. 6A-6Bcan include an array of solid state light emitting diodes arranged in apattern to produce an appropriate intensity distribution over a surfaceof an object. In addition to having a controller with the capability tomonitor and maintain the light intensity provided to the surface towithin a predetermined variation level, it is understood that thedistance between the array 38 of radiation sources 40 and the objectundergoing irradiation can be varied to a set of possible distances thathave been predetermined to achieve a low variation in light intensityover the surface of the object. It is understood that the type ofradiation sources including the type of light sources is variable, andthe example provided above is not meant to limit the various embodimentsdescribed herein. Furthermore, it is understood that other radiationsources 40 in the array 38 can be used besides ultraviolet radiationsources and light sources. For example, the array 38 can includefluorescent radiation sources.

FIG. 7 shows an example of a spectral power density that can be obtainedfrom a lighting system described herein that has the capability tocontrol light intensity at a surface of an object according to anembodiment. In FIG. 7, the spectral power density was obtained from alighting system using ultraviolet radiation sources that irradiated thesurface of an object with UV-A and UV-B radiation, and visible lightsources that irradiated the surface with blue light, green light and redlight. The presence of these sources are shown by the peaks in thespectral power density of FIG. 7. In particular, the spectral powerdensity of FIG. 7 shows a UV-B peak wavelength of 295 nm with a fullwidth half max ranging from 10 nm to 20 nm, a UV-A peak wavelength ofabout 370 nm, a blue light peak wavelength at about 450 nm, a greenlight peak wavelength at about 530 nm, and a red light peak wavelengthat about 660 nm.

A spectral power density with this light intensity distribution providesa spectra that improves plant growth, plant health, and plant medicinaland/or antioxidant value, for a consumer. An object such as a plant thatis irradiated with a lighting system that can provide such a lightintensity distribution will have an effect on the plant in that theplant will have higher antioxidants and flavonoids as opposed to plantradiation with a different spectra. An important property of thedisclosed spectra shows the intensity values of ultraviolet radiation inrelation to visible radiation intensity values. It is understood that alighting system using other radiation sources and/or alternative typesof ultraviolet radiation sources and visible light sources operating atother parameter values can be used to attain similarly beneficialresults. For example, in one embodiment, the peak wavelength of UV-B canrange from 280 nm to 310 nm.

FIG. 8 shows another example of a spectral power density obtained from alighting system described herein that has the capability to controllight intensity at a surface of an object according to an embodiment. Inthis example, the spectral power density of FIG. 8 was obtained from alighting system using ultraviolet radiation sources that irradiated thesurface of an object with UV-A radiation, that comprise UV-A lightemitting diodes, with two other peaks being correspondingly blue and redpeaks. The presence of these sources are shown by the peaks in thespectral power density of FIG. 8. In particular, the spectral powerdensity of FIG. 8 shows a UV-A peak wavelength of 370 nm, a blue peakwavelength of 450 nm, and a red peak wavelength at 650 nm.

FIG. 8 also shows the spectral power density obtained from the lightingsystem in relation to the spectral power density obtained fromirradiating the surface of the object with solar irradiance. As shown inFIG. 8, the ultraviolet radiation spectra and blue and red spectra areamplified to improve plant health and increase plant growth. Thecurrently selected spectra is obtained through research andexperimentation to improve plant characteristics for various plant typesand in particular for medicinal plants from the Cannabaceae family.Similar to FIG. 7, it is understood that for this embodiment, a lightingsystem using other radiation sources and/or alternative types ofultraviolet radiation sources and visible light sources operating atother parameter values can be used to attain similarly beneficialresults.

FIGS. 9A-9B show a schematic of the lighting system 10 depicted in FIG.1 irradiating a plant 42 including its canopy of leaves 44 according toan embodiment. In the embodiments illustrated in FIGS. 9A-9B, thecontroller 22 of the lighting system 10 can use measurements from thelight sensors 20 to ensure that the array 16 of ultraviolet radiationsources 18 irradiates the canopy of leaves 44 in the plant 42 with auniform distribution of light intensity. Although FIG. 9A shows thelighting system 10 positioned above the plant 42, it is understood thatthe lighting system can be located and positioned in other orientationswith respect to the plant and the canopy of leaves 44. For example, inone embodiment, the lighting system 10 can have a distributed designwhere the ultraviolet radiation sources and sensors do not have to bephysically adjacent to each other. In an embodiment, the ultravioletradiation source can comprise a mesh that can be located above or withinthe canopy of plant leaves. In this manner, the lighting system 10 witha distributed design can be located within the plant canopy.

In general, regardless of whether the lighting system 10 is positionedabove the canopy of leaves 44 or in some other position such as withinthe canopy, irradiation of the canopy of leaves can be a complicatedtask for the controller 22 to facilitate a uniform distribution of lightintensity. In particular, due to the three-dimensional nature of theplant canopy, not all of the leaves will receive the same dose even ifthe distribution of intensity over some imaginary surface that crossesthe canopy is uniform.

In order to address this challenge, the controller 22 can be configuredto recognize domains of the leaves 44 as two-dimensional projections. Asused herein, recognizing domains of the leaves 44 as two-dimensionalprojections means locating the domains comprising the surfaces of leavesin three dimensional space. In this manner, the controller 22 cancontrol the ultraviolet radiation sources 18 based on the light sensor20 feedback to deliver the radiation at a direction and intensity thatis uniform to all of the leaves in each domain. Since the projections oftwo-dimensional domains of leaves maps to the three-dimensional natureof the plant canopy, all of the leaves 44 in the canopy will receive auniform distribution of light intensity.

In order to ensure that all of the two-dimensional domains of leavesreceive an optimal light distribution such as a uniform light intensitydistribution, the controller 22 can implement an algorithm thatdetermines the distribution of an optimal intensity over a surface. Inone embodiment, the algorithm can begin by first determining theposition of the leaves in each of the domains using reflected lightmeasurements received from the light sensors 20. In particular, thepositions of leaves are determined by partitioning the space intosubdomains (such as finite elements) and determining if each subdomainbelongs to a surface of a leaf or not. After determining the positionsof the leaves in each two-dimensional domain, the controller 22 can thenrecord the coordinates that cover the two-dimensional image of theleaves in the domain.

Next, the controller 22 can direct the ultraviolet radiation sources toirradiate the surface area of the leaves 44 on the plant 42 thatcorresponds to each two-dimensional domain with light intensity having apeak distribution. In one embodiment, the light intensity with peakdistribution can be directed to the center of the leaves using a setwavelength for the illumination. The light sensors 20 can measure thelight intensity distribution over each of the leaves 44 that correspondsto a two-dimensional domain. The controller 22 can also record the lightintensity measurements over the leaves in each two-dimensional domain.

The controller 22 can then compare the light intensity distribution overthe leaves in each two-dimensional domain to a desired target intensitydistribution stored in memory. In one embodiment, the desired targetintensity distribution can include, but is not limited to, thecoloration of the leaf, the type of leaf (size and location on the stemof the plant), etc. If the desired target intensity distribution overthe leaves domain is achieved, then the intensity distribution over thesurface of the leaves is deemed to be found, recorded in memory, and theprocess of determining the optimal intensity distribution over a surfaceencompassing the leaves for a particular domain is terminated.Alternatively, if the desired target intensity distribution is notattained, then the controller can instruct the power component 24 tochange the power of the ultraviolet radiation sources irradiating thatdomain to adjust the intensity over the leaves in the domain. Thecomparison of light intensity measurements and adjusting of the lightintensity can continue until the controller determines that the domainhas achieved the desired target intensity distribution. The processwould be similar for all of the other two-dimensional leave domains thatform the canopy of leaves 44.

With all of the settings determined for effectuating optimal irradiationof the canopy of leaves 44, the lighting system 10 can use thesesettings to globally irradiate other plants in a controlled environmentsuch as, for example, a greenhouse. These settings can also be specifiedfor types of plants during different periods of plant growth. Forexample, the different periods of plant growth can include, but are notlimited to, a plant seedling period, a plant development period, a plantmaturity period, plant blooming period and a plant fruition period. Itis understood that the optimal irradiation settings can also bespecified for different parts of the plant and not just the canopy ofleaves 44. For example, specific parts of the leaves 44 or sections ofthe plant 42 such as the trunk or roots can have vastly differentirradiation conditions, and can thus have different settings which canbe ascertained in a like manner.

It is understood that for a three-dimensional structure, the complexityof illumination can be due to reflection and scattering from othersurfaces presented in a surrounding environment. Thus, both the powerand the direction of the radiation that is emitted from the array 16 ofultraviolet radiation sources 18 can be adjusted until the optimalconfiguration of intensity is found. For example, the ultravioletradiation sources 18 can be configured to have a directional degree offreedom (within a range) in order to radiate a surface at a directioncharacterized by two surface angles. In addition, in one embodiment, thelighting system 10 can be implemented with ultraviolet radiation sources18 having the capability for lateral motion along a mounting surface ofthe system. In one embodiment, the ultraviolet radiation sources 18 canbe configured as a lamp fixture in order to provide further control ofintensity that can be directed to the canopy of leaves 44. It isunderstood, that the ultraviolet radiation sources 18 can be positionedat a density that is variable through the mounting surface. Forinstance, more of the ultraviolet radiation sources 18 can be positionedon the periphery of the mounting surface of the lamp fixture in order toprovide a focused light intensity distribution to the area of the canopythat would be irradiated by such sources. Further, although theembodiment depicted in FIGS. 9A-9B is discussed only with regard to theultraviolet radiation sources 18 and the light sensors 20, it isunderstood that the lighting system 10 can be implemented with any ofthe other aforementioned radiation sources (e.g., visible light sources,infrared radiation sources, fluorescent sources) and sensors (e.g.,environment condition sensors, fluorescent sensors).

FIGS. 10A and 10B show an illustrative operation scenario in whichmultiple sets of ultraviolet radiation sources, such as for example, aset of UV-B sources and at least one of UV-A sources or blue-UV sourcesare operated as a function of time to irradiate food items forfacilitating food safety, enhancing food preservation and controllinginsects according to an embodiment. As shown in FIG. 10A, a set ofblue-UV sources radiation sources can initially emit blue-UV radiationat a constant intensity 15D.

During this time, the controller 22 can determine whether anymicroorganisms are present (e.g., a level of microorganism activity) onthe surface of food being illuminated. For example, the controller 22can evaluate an amplitude of a fluorescent signal sensed by afluorescent sensor, visual data from a visual camera, and/or the like.To this extent, the blue-UV radiation can elicit a fluorescent signalwhen microbial activity is present on the surface of the food item.Alternatively, the surface can be periodically irradiated with UV-Bradiation that is capable of eliciting a fluorescent signal if microbialactivity is present. Regardless, the controller 22 can determine a levelof microbial activity based on an amplitude of the fluorescent signalsensed by a fluorescent sensor as indicated by reference 17 in FIG. 10B.The surface can be irradiated by the blue-UV radiation over a prolongedperiod of time that ranges from tens of minutes to tens of hours whilethe controller 22 periodically evaluates a level of a fluorescent signalto determine the level of microorganism activity. To this extent, thecontroller 22 can periodically operate the fluorescence sensor tomonitor the amount of contamination present on the surface of the food.

In this example, FIG. 10B shows a sharp increase in the growth ofmicroorganism activity as noted by reference element 17. At time t, thelevel of microorganism activity crosses a predetermined contaminationthreshold 19 indicative of a need for more intense ultravioletirradiation treatment due to rapid growth of microbial activity on thefood items. In response, as shown in FIG. 10A, the controller 22 canoperate another set of ultraviolet radiation sources to emit ultravioletradiation 15A (e.g., UV-B radiation) to perform the more intenseultraviolet irradiation treatment at a short burst of intensity thatlasts at most a few minutes. In this manner, ultraviolet radiation 15Agenerated by the UV-B sources can bring the microbial activity withinappropriate limits by rapidly suppressing microbial activity on thesurface of the food. The blue-UV radiation 15D emitted by the blue-UVsource can be used to maintain microbial activity within limits over anextended period of time, while the ultraviolet radiation 15A emitted bythe UV-B sources can be designed to rapidly suppress microbial activity.

As noted above, the lighting systems described herein can be implementedto operate in a variety of locations for instances in which the systemsare utilized to irradiate food items for purposes of facilitating foodsafety, food preservation, and/or control insect infestation. Examplesof possible locations that the lighting systems can be implementedinclude, but are not limited to, a refrigerator, a food storagecontainer, a kitchen countertop, a food manufacturing or processingfacility, transportation containers, etc. In general, the lightingsystems can be configured to operate with any food storage containerthat stores or holds for long or short periods of time, food items thatare susceptible to microorganisms, contaminants and the like that canaffect the food safety, preservation, and quality of these items.Examples of a food storage container can include, but are not limitedto, a receptacle, a vessel, a repository, a canister, and foodconveying, manufacturing, and processing mechanisms.

FIG. 11 shows a block diagram illustrating operating configurations fora lighting system with ultraviolet radiation sources 51 that canirradiate food items in a food storage container according to anembodiment. As illustrated, the controller 22 can use data correspondingto a selected operating configuration 50A-50C to adjust one or moreaspects of the ultraviolet radiation 46 generated by the ultravioletradiation sources 51. In an embodiment, the operating configurations50A-50C can include a storage life preservation operating configuration50A, a disinfection operating configuration 50B, and an ethylenedecomposition operating configuration 50C. In an embodiment, the storagelife preservation operating configuration 50A is configured to increasea storage lifespan of items stored within the container, while thedisinfection operating configuration 50B is configured to eliminateand/or decrease an amount of microorganisms present within the containeror on item(s) located within the container. The ethylene decompositionoperating configuration 50C can be configured to remove ethylene fromthe atmosphere of the container, which would otherwise decrease thestorage lifespan of items located within the container. One or more ofthese operating configurations can be configured to improve and/ormaintain the visual appearance and/or nutritional value of the fooditems within the container. For example, increasing the storage lifespancan include suppressing microorganism growth, maintaining and/orimproving nutritional value, maintaining and/or improving visualappearance, and/or the like. Also, the operating configurations can beconfigured to prevent the build-up of mold within the storage areaand/or on the items within the storage area.

The controller 22 can be configured to control and adjust a direction,an intensity, a pattern, and/or a spectral power (e.g., wavelength) ofthe UV sources 51 to correspond to a particular operating configuration50A-50C. The controller 22 can also control and adjust each property ofthe UV sources 51 independently. For example, the controller 22 canadjust the intensity, the time duration, and/or time scheduling (e.g.,pattern) of the UV sources 51 for a given wavelength. Each operatingconfiguration 50A-50C can designate a unique combination of: a targetultraviolet wavelength, a target intensity level, a target pattern forthe ultraviolet radiation (e.g., time scheduling, including duration(e.g., exposure/illumination time), duty cycle, time betweenexposures/illuminations, and/or the like), a target spectral power,and/or the like, in order to meet a unique set of goals corresponding toeach operating configuration 50A-50C.

For the storage life preservation operating configuration 50A, a targetwavelength range can be approximately 285 nm to approximately 305 nm.The wavelength is specified in terms of its peak emission, and acharacteristic half width of the emission can be approximately 1 nm toapproximately 30 nm. The target intensity range for the storage lifeprolongation operating configuration 50A can be approximately 0.1milliwatts/m² to approximately 1000 milliwatts/m². For the disinfectionoperating configuration 50B, a target wavelength range can beapproximately 250 nm to approximately 285 nm. The wavelength isspecified in terms of its peak emission, and a characteristic half widthof the emission can be approximately 1 nm to approximately 35 nm. Thetarget intensity range for the disinfection operating configuration 50Bcan be approximately 1 milliwatt/m² to approximately 10 watts/m². Forthe ethylene decomposition operating configuration 50C, the targetwavelength range can be approximately 230 nm to approximately 260 nm.The wavelength is specified in terms of its peak emission, and acharacteristic half width of the mission can be approximately 1 nm toapproximately 30 nm. The target intensity range for the ethylenedecomposition operating configuration 50C can be approximately 1milliwatt/m² to approximately 1000 watts/m².

FIG. 12 shows an illustrative lighting system 52 including ultravioletradiation sources 51 and other sources that can irradiate food items 56in a food storage container 53 according to an embodiment. In thisembodiment, the controller 22 is configured to control the UV sources 51to direct ultraviolet radiation 46 into the storage container 53, withinwhich a set of food items 56 are located. A feedback component 54 isconfigured to acquire data used to monitor a set of current conditionsof the storage container 53 and/or the items 56 over a period of time.As illustrated, the feedback component 54 can include a plurality ofsensing devices 58, each of which can acquire data used by thecontroller 22 to monitor the set of current conditions.

In an embodiment, the sensing devices 58 can include at least one of avisual camera or a chemical sensor. The visual camera can acquire data(e.g., visual, electronic, and/or the like) used to monitor the foodstorage container 53 and/or one or more of the items 56 located therein,while the chemical sensor can acquire data (e.g., chemical, electronic,and/or the like) used to monitor the storage container 53 and/or one ormore of the items 56 located therein. The set of current conditions ofthe storage container 53 and/or items 56 can include the color or visualappearance of the items 56, the presence of microorganisms within thestorage container 53, and/or the like. In an embodiment, the visualcamera comprises a fluorescent optical camera. In this case, when thecontroller 22 is operating the UV radiation sources 51 in the storagelife preservation operating configuration 50A (FIG. 11), the visualcamera can be operated to detect the presence of microorganisms as theyfluoresce in the ultraviolet light. In an embodiment, the chemicalsensor is an infrared sensor, which is capable of detecting anycombination of one or more gases, such as ethylene, ethylene oxide,and/or the like. However, it is understood that a visual camera and achemical sensor are only illustrative of various types of sensors thatcan be implemented. For example, the sensing devices 58 can include oneor more mechanical sensors (including piezoelectric sensors, variousmembranes, cantilevers, a micro-electromechanical sensor or MEMS, ananomechanical sensor, and/or the like), which can be configured toacquire any of various types of data regarding the storage container 53and/or items 56 located therein.

In the ethylene decomposition operating configuration 50C (FIG. 11), thestorage container 53 can include a high efficiency ethylene destructionchamber 55 that includes a high UV reflectivity, high UV intensityradiation chamber for chemical (e.g., ethylene) destruction. In thisembodiment, the controller 22 can operate the one or more devices in thechamber 55 to destroy ethylene, which may be present within theatmosphere of the storage container 53. The controller 22 can separatelymonitor the ethylene levels and the level of microorganism activity.

The feedback component 54 also can include one or more additionaldevices. For example, the feedback component 54 is shown including alogic unit 57. In an embodiment, the logic unit 57 receives data from aset of sensing devices 58 and provides data corresponding to the set ofconditions of the storage container 53 and/or items 56 located in thestorage container 53 for processing by the controller 22. In a moreparticular embodiment, the controller 22 can provide informationcorresponding to the currently selected operating configuration 50(e.g., 50A, 50B, 50C in FIG. 11) for use by the feedback component 54.For example, the logic unit 57 can adjust the operation of one or moreof the sensing devices 58, operate a unique subset of the sensingdevices 58, and/or the like, according to the currently selectedoperating configuration 50. In response to data received from thefeedback component 54, the controller 22 can automatically adjust andcontrol one or more aspects of the ultraviolet radiation 46 generated bythe ultraviolet radiation sources 51 according to the currently selectedoperating configuration 50.

In the ethylene decomposition operating configuration 50C, the storagecontroller 22 can include a catalyst 59 for reducing ethylene levelswithin the storage container 53, e.g., via a photocatalytic reaction.The catalyst 59 can include titanium dioxide, and/or the like. Thecatalyst 59 also can be configured to chemically inactivate or absorbthe ethylene gas. In an embodiment, the controller 22 can operate one ormore devices of an environmental control component 60 in order toselectively introduce the catalyst 59 into the storage container 53. Inanother embodiment, the environmental control component 60 canautomatically introduce the catalyst 59 into the storage container 53according to a target level of the catalyst 59 and/or a preset schedule.

In an embodiment, the lighting system 52 can include visible and/orinfrared (IR) sources 62 which can be controlled by the controller 22 togenerate light 63 directed within the storage container 53. For example,the controller 22 can control a visible source to generate light 63 withwavelengths configured to increase photosynthesis in one or more fooditems 56. Additionally, the controller 22 can control an IR source togenerate light 63 directed onto certain foods to locally increase thetemperature of the food items 56. The visible and/or IR sources 62 alsocan generate light 63 to excite fluorescence from microorganisms thatmay be present on items 56, so that a sensing device 58 of the feedbackcomponent 54 can detect the microorganisms. Furthermore, the visibleand/or IR sources 62 can generate light 63 to facilitate a target (e.g.,optimal) photocatalytic reaction for the catalyst 59.

FIGS. 13A-13C show examples of various types of storage containers 53 inwhich a lighting system with ultraviolet radiation sources 51 canirradiate food items according to embodiments. As shown in FIG. 13A, thestorage container can be a refrigerator and/or freezer that stores aplurality of food items 56. In another embodiment, as shown in FIG. 13B,the storage container 53 can be a cooler. In still another embodiment,as shown in FIG. 13C, the storage container 53 can be a pantry (e.g., ashelf in the pantry), and/or the like. In each case, a lighting systemwith ultraviolet radiation sources as described herein can beimplemented in conjunction therewith using any solution. To this extent,it is understood that embodiments of the lighting system can varysignificantly in the number of devices, the size of the devices, thepower requirements for the system, and/or the like. Regardless, it isunderstood that these are only exemplary storage containers and that thelighting system of the various embodiments described herein may beapplicable to other storage devices not specifically mentioned.

FIG. 14 shows a food storage container 53 in which ultraviolet radiationsources 51 are positioned in various locations about the storagecontainer according to an embodiment. In an embodiment, the ultravioletradiation sources 51 can include a plurality of ultraviolet lightemitters located in various locations adjacent about an internal area 64of the storage container 53. FIG. 14, which provides a partialcross-sectional perspective view of the storage container 53 can have atleast one food item 56 in the internal area 64. As shown in FIG. 14, aplurality of ultraviolet radiation sources 51 such as UV emitters can belocated within the internal area 64 of the storage container 53. In oneembodiment, the storage container 53 can comprise multiple layers. Thelayers can protect other storage areas and/or components of the storagecontainer 53 from ultraviolet radiation and/or increase the efficiencyof the ultraviolet radiation within the internal area 64. The layers donot allow UV radiation to escape from the internal area 64.

For example, an ultraviolet transparent wall 66 can surround theinternal storage area 64 within which the ultraviolet radiation emittersare located. A hollow region 68 can be located between the ultraviolettransparent wall 66 and a highly reflective wall 70. The highlyreflective wall 70 can reflect and/or absorb the UV radiation. Thehighly reflective wall 70 can include a reflectivity of more thanapproximately 50% as measured for the UV radiation at the normalincidence direction. Approximately 20% of the volume of the hollowregion 68 can include a refractive index lower than that of theultraviolet transparent wall 66. A plurality of elements 72 can protrudefrom the ultraviolet transparent wall 66 into the hollow region 68. Theplurality of elements 72 can include high/low index interfaces 74.During operation, once the ultraviolet radiation emitters shineultraviolet light into the internal area 64, the high/low indexinterfaces 74 and the highly reflective wall 70 reflect ultravioletlight back into the internal storage area 64. The ultraviolettransparent wall 66 can be made of one or more materials that allowultraviolet radiation to pass through, such as fused silica, anamorphous fluoroplastic (e.g., Teflon by Dupont), and/or the like. Otherillustrative materials include alumina sol-gel glass, alumina aerogel,sapphire, aluminum nitride (e.g., single crystal aluminum nitride),boron nitride (e.g., single crystal boron nitride), and/or the like. Theouter reflective wall 70 can be made of one or more materials thatreflects ultraviolet radiation, such as polished aluminum, a highlyultraviolet reflective expanding polytetrafluoroethylene (ePTFE)membrane (e.g., GORE® Diffuse Reflector Material), and/or the like.

FIGS. 15A and 15B show illustrative cylindrical-shaped food storagecontainers 76 that can deploy a lighting system with ultravioletradiation sources 51 to irradiate food items 56 stored in the containersaccording to embodiments. In these embodiments, the cylindrical shape ofthe storage containers 76 can allow for increased reflectivity ofultraviolet radiation back into a storage area 78 of the containers andonto the stored items 56 from various sides/angles. Furthermore, thecylindrical shape can increase the surface area of items 56 that areexposed to ultraviolet radiation. The cylindrical shaped storagecontainers 76 can be utilized to store, for example, medium sized roundfood items, such as apples, tomatoes, and/or the like. However, it isunderstood that the storage containers 76 can include any shape andsize.

The storage containers 76 of FIGS. 15A and 15B can further include asliding door 80 for access to the storage area within which items 56 maybe located. Although not depicted in FIGS. 15A and 15B, a controller canbe configured to control the ultraviolet radiation sources 51, such thatwhen sliding door 80 is opened, the ultraviolet radiation sources areturned off. Once the sliding door 80 is closed, the ultravioletradiation sources 51 are turned back on. Again, although not shown inFIGS. 15A and 15B, the storage container 76 may also include an innerultraviolet radiation transparent enclosure and an outer ultravioletradiation reflective wall, as shown and described herein. Furthermore,the storage containers 76 can include a shelf 82 for supporting the fooditems 56. In an embodiment, the shelf 80 is formed of an ultravioletradiation transparent material so that the items 56 located on the shelf80 can be subjected to ultraviolet radiation from any direction.

FIG. 16 shows an illustrative storage container 84 with a plurality ofsub-compartments 86 (86A, 86B, 86C) that can deploy a lighting systemwith ultraviolet radiation sources to irradiate food items according toan embodiment. In the embodiment depicted in FIG. 16, thesub-compartments 86 (86A, 86B, 86C) of the storage container 84 can beindividually/separately monitored by a controller 22 using a feedbackcomponent 54 as described with respect to FIG. 12. It is understood thatthe plurality of sub-compartments 86 (86A, 86B, 86C) can be locatedwithin an inner ultraviolet radiation transparent enclosure, such as theone shown in FIG. 14. Furthermore, the ultraviolet radiation sources 51in each sub-compartment can be individually controlled by the controller22. For example, a shelf 88 can be partitioned into a firstsub-compartment 86A and a second sub-compartment 86B, which areseparated by a divider 90. Each of the sub-compartments 86A, 86B, 86Ccan include the same type of UV sources 51.

Alternatively, as shown in FIG. 16, the first sub-compartment 86A caninclude a first type of UV sources 51A, and the second sub-compartment86B can include a second type of UV sources 51B. The controller 22 cancontrol the UV sources 51A, 51B, such that the first sub-compartment 86Ais subjected to a first operating configuration and the secondsub-compartment 86B is subjected to a second operating configuration.The particular operating configuration for each sub-compartment candiffer. Furthermore, the controller can control the UV sources 51A tohave a first intensity and a first wavelength, and control the UVsources 51B to have a second intensity and a second wavelength. Forexample, the UV sources 51A can include a full intensity, while the UVsources 51B can includes zero intensity. Conversely, the UV sources 51Acan include a zero intensity, while the UV sources 51B can include afull intensity. Furthermore, the controller 22 can independently tunethe relative intensities of each of the UV sources 51A, 51B, and eitherof the UV sources 51A, 51B can have any intensity between zero and full.

Additionally, the shelves 88 may revolve, e.g., via a motor 92. Themotor 92 may be controlled by the controller 22 and rotate according toa timing schedule, such that the first sub-compartment 86A and thesecond sub-compartment 86B each receive ultraviolet light emitted by oneof the UV sources 51A, 51B according to a particular operatingconfiguration at a specific time. Although the UV sources 51A, 51B areshown as mounted above the shelves 88, it is understood that UV sourcescan also be within the shelves 88, below the shelves 88, and/or thelike.

U.S. Pat. No. 9,795,699 provides additional details of the food storagecontainers and lighting systems depicted in FIGS. 11-16 that can be usedto irradiate food items stored in the containers. U.S. Pat. Nos.9,034,271; 9,919,068; 10,383,964; 9,724,441; 10,172,968; 10,272,168;9,750,830; 9,179,703; 9,707,307; 9,878,061; and 9,981,051 also provideadditional details of food storage containers and lighting systems thatcan be deployed with the embodiments described herein to irradiate fooditems for purposes of facilitating food safety, food preservation,enhancing food quality and insect control.

Referring now to FIG. 17, there is a schematic block diagramrepresentative of an overall processing architecture of a lightingsystem 800 for irradiating a light sensitive object. In this embodiment,the architecture of the lighting system 800 is shown including theradiation sources 802 (e.g. ultraviolet radiation sources, visible lightsources, infrared sources, fluorescent sources) and the sensors 804(e.g., light sensors, environment condition sensors, fluorescentsensors) for the purposes of illustrating the interaction of all of thecomponents that can be used to provide a lighting system for irradiatinga light sensitive object.

As depicted in FIG. 17 and described herein, the system 800 can includea controller 22. In one embodiment, the controller 22 can be implementedin the form of a control unit embodying a computer system 820 includingan analysis program 830, which makes the computer system 820 operable tomanage the radiation sources 802 and the sensors 804 in the mannerdescribed herein. In particular, the analysis program 830 can enable thecomputer system 820 to operate the radiation sources 802 to directradiation towards the object and process data obtained during operationwhich is stored as data 840. The computer system 820 can individuallycontrol each source 802 and sensor 804 and/or control two or more of thesources and the sensors as a group. Furthermore, the radiation sourcescan emit radiation of substantially the same wavelength or of multipledistinct wavelengths.

In an embodiment, during an initial period of operation, the computersystem 820 can acquire data from at least one of the sensors 804regarding one or more attributes used by the lighting system andgenerate data 840 for further processing. The computer system 820 canuse the data 840 to control one or more aspects of the radiationgenerated by the radiation sources 802 during testing and operationalmodes.

Furthermore, one or more aspects of the operation of the radiationsources 802 can be controlled or adjusted by a user 812 via an externalinterface I/O component 826B. The external interface I/O component 826Bcan be used to allow the user 812 to selectively turn on/off theradiation sources 802.

The external interface I/O component 826B can include, for example, atouch screen that can selectively display user interface controls, suchas control dials, which can enable the user 812 to adjust one or moreof: an intensity, and/or other operational properties of the set ofradiation sources 802 (e.g., operating parameters, radiationcharacteristics). In an embodiment, the external interface I/O component826B could conceivably include a keyboard, a plurality of buttons, ajoystick-like control mechanism, and/or the like, which can enable theuser 812 to control one or more aspects of the operation of the set ofradiation sources 802 and sensors 804. The external interface I/Ocomponent 826B also can include any combination of various outputdevices (e.g., an LED, a visual display), which can be operated by thecomputer system 820 to provide status information for use by the user812. For example, the external interface I/O component 826B can includeone or more LEDs for emitting a visual light for the user 812, e.g., toindicate a status of the irradiation of the samples. In an embodiment,the external interface I/O component 826B can include a speaker forproviding an alarm (e.g., an auditory signal), e.g., for signaling thatultraviolet radiation is being generated or that an irradiation hasfinished.

The computer system 820 is shown including a processing component 822(e.g., one or more processors), a storage component 824 (e.g., a storagehierarchy), an input/output (I/O) component 826A (e.g., one or more I/Ointerfaces and/or devices), and a communications pathway 828. Ingeneral, the processing component 822 executes program code, such as theanalysis program 830, which is at least partially fixed in the storagecomponent 824. While executing program code, the processing component822 can process data, which can result in reading and/or writingtransformed data from/to the storage component 824 and/or the I/Ocomponent 826A for further processing. The pathway 828 provides acommunications link between each of the components in the computersystem 820. The I/O component 826A and/or the external interface I/Ocomponent 826B can comprise one or more human I/O devices, which enablea human user 812 to interact with the computer system 820 and/or one ormore communications devices to enable a system user 812 to communicatewith the computer system 820 using any type of communications link. Tothis extent, during execution by the computer system 820, the analysisprogram 830 can manage a set of interfaces (e.g., graphical userinterface(s), application program interface, and/or the like) thatenable human and/or system users 812 to interact with the analysisprogram 830. Furthermore, the analysis program 830 can manage (e.g.,store, retrieve, create, manipulate, organize, present, etc.) the data,such as data 840, using any solution.

In any event, the computer system 820 can comprise one or more generalpurpose computing articles of manufacture (e.g., computing devices)capable of executing program code, such as the analysis program 830,installed thereon. As used herein, it is understood that “program code”means any collection of instructions, in any language, code or notation,that cause a computing device having an information processingcapability to perform a particular function either directly or after anycombination of the following: (a) conversion to another language, codeor notation; (b) reproduction in a different material form; and/or (c)decompression. To this extent, the analysis program 830 can be embodiedas any combination of system software and/or application software.

Furthermore, the analysis program 830 can be implemented using a set ofmodules 832. In this case, a module 832 can enable the computer system820 to perform a set of tasks used by the analysis program 830, and canbe separately developed and/or implemented apart from other portions ofthe analysis program 830. When the computer system 820 comprisesmultiple computing devices, each computing device can have only aportion of the analysis program 830 fixed thereon (e.g., one or moremodules 832). However, it is understood that the computer system 820 andthe analysis program 830 are only representative of various possibleequivalent monitoring and/or control systems that may perform a processdescribed herein with regard to the control unit, the sources and thesensors. To this extent, in other embodiments, the functionalityprovided by the computer system 820 and the analysis program 830 can beat least partially be implemented by one or more computing devices thatinclude any combination of general and/or specific purpose hardware withor without program code. In each embodiment, the hardware and programcode, if included, can be created using standard engineering andprogramming techniques, respectively. Illustrative aspects of theinvention are further described in conjunction with the computer system820. However, it is understood that the functionality described inconjunction therewith can be implemented by any type of monitoringand/or control system.

Regardless, when the computer system 820 includes multiple computingdevices, the computing devices can communicate over any type ofcommunications link. Furthermore, while performing a process describedherein, the computer system 820 can communicate with one or more othercomputer systems, such as the user 812, using any type of communicationslink. In either case, the communications link can comprise anycombination of various types of wired and/or wireless links; compriseany combination of one or more types of networks; and/or utilize anycombination of various types of transmission techniques and protocols.

All of the components depicted in FIG. 17 can receive power from a powercomponent 24. The power component 24 can take the form of one or morebatteries, a vibration power generator that can generate power based onmagnetic inducted oscillations or stresses developed on a piezoelectriccrystal, a wall plug for accessing electrical power supplied from agrid, and/or the like. In an embodiment, the power source can include asuper capacitor that is rechargeable. Other power components that aresuitable for use as the power component can include solar, a mechanicalenergy to electrical energy converter such as a piezoelectric crystal, arechargeable device, etc.

The foregoing description of various aspects of the invention has beenpresented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed, and obviously, many modifications and variations arepossible. Such modifications and variations that may be apparent to anindividual in the art are included within the scope of the invention asdefined by the accompanying claims.

What is claimed is:
 1. A lighting system, comprising: an array ofultraviolet radiation sources configured to irradiate a surface of alight sensitive object with ultraviolet radiation having a wavelengthrange that includes ultraviolet-A (UV-A) radiation, ultraviolet-B (UV-B)radiation and blue-ultraviolet (blue-UV) radiation, wherein each of theultraviolet radiation sources irradiates the surface of the object at atarget radiation over a predetermined wavelength range, at least one ofthe ultraviolet radiation sources operates at a peak wavelength that iswithin a UV-B wavelength range, and wherein at least one of theultraviolet radiation sources operates at a peak wavelength that iswithin at least one of the UV-A wavelength range or the blue-UVwavelength range; a plurality of light sensors configured to measurelight intensity at the surface of the object, wherein each light sensormeasures light intensity in a wavelength range that corresponds to thepredetermined wavelength range emitted from one of the ultravioletradiation sources in the array; and a controller configured to controlthe light intensity over the surface of the object as a function oflight intensity measurements obtained from the light sensors, whereinthe controller uses the light intensity measurements to determinewhether each ultraviolet radiation source is illuminating the surface ofthe object at a dose that delivers the ultraviolet radiation at anintensity that is within an acceptable variation with a predeterminedlight intensity value, the controller adjusting the power of anultraviolet radiation source in response to determining that theultraviolet radiation source is illuminating the surface with anintensity that has an unacceptable variation with the predeterminedlight intensity value targeted for the surface, each ultravioletradiation source that is adjusted in power delivers an adjusted dose ofthe ultraviolet radiation that is a function of an amount of theunacceptable variation with the predetermined light intensity value. 2.The lighting system of claim 1, wherein the acceptable variation withthe predetermined intensity value is at most 5%.
 3. The lighting systemof claim 1, wherein the dose is in the range of 0.1 kJ/m² to 20 kJ/m².4. The lighting system of claim 1, wherein each of the ultravioletradiation sources in the array delivers ultraviolet radiation to thesurface of the object in short pulses.
 5. The lighting system of claim4, wherein each pulse of ultraviolet radiation generated from anultraviolet radiation source is less than an amount of time needed forachieving a steady state temperature of operating the ultravioletradiation source.
 6. The lighting system of claim 1, wherein the arrayof ultraviolet radiation sources is configured for movement about theobject, wherein the movement includes both translational and directionaldegrees of freedom.
 7. The lighting system of claim 1, wherein the arrayof ultraviolet radiation sources irradiates the surface of the objectfor a predetermined duration that is no more than six hours per day. 8.The lighting system of claim 1, wherein the array of ultravioletradiation sources includes a greater amount of ultraviolet radiationsources located at side portions of the array in comparison to an amountof ultraviolet radiation sources located near a central region of thearray, wherein the side portions include at least 10% more ultravioletradiation sources than the amount of ultraviolet radiation sourceslocated near the central region.
 9. The lighting system of claim 8,wherein the ultraviolet radiation sources located at the side portionsof the array operate at a higher pulsed frequency than the ultravioletradiation sources located near the central region.
 10. The lightingsystem of claim 8, wherein the ultraviolet radiation sources located atthe side portions of the array operate at a higher power than theultraviolet radiation sources located near the central region.
 11. Thelighting system of claim 1, further comprising a plurality offluorescent sources to irradiate the surface of the object inconjunction with the ultraviolet radiation sources.
 12. The lightingsystem of claim 11, further comprising a plurality of fluorescentsensors to detect fluorescent radiation reflected from the surface ofthe object, wherein the fluorescent sources and the fluorescent sensorsoperate in a pulsed regime to differentiate from fluorescent signalsreflected from the surface that arise from the irradiation by theultraviolet radiation sources.
 13. The light sensing system of claim 1,wherein at least one of the light sensors comprises a visible camera.14. A lighting system, comprising: an array of ultraviolet radiationsources configured to irradiate a surface of a light sensitive surfaceobject with ultraviolet radiation, wherein the ultraviolet radiationsources can operate in a predetermined wavelength that includes at leastone of: a UV-A radiation wavelength range or a UV-B radiation wavelengthrange, wherein at least one of the ultraviolet radiation sources canoperate at a peak wavelength that is within a wavelength range from 315nm to 400 nm; a light sensor configured to measure light intensity atthe surface of the object, wherein the light sensor measures lightintensity in a wavelength range that corresponds to the predeterminedwavelength range emitted from at least one of the ultraviolet radiationsources in the array; and a controller configured to detect a change inthe object by using data feedback from the light sensor and control thelight intensity over the surface of the object, wherein the controllerreceives light intensity signals from the light sensor and determineswhether the light intensity at the surface of the object exceeds anacceptable variation with a predetermined intensity value, thecontroller adjusting the power of an ultraviolet radiation source inresponse to determining that the light intensity at the surface of theobject exceeds the acceptable variation with the predetermined intensityvalue, each ultraviolet radiation source that is adjusted in powerdelivers an adjusted dose of the ultraviolet radiation that is afunction of an amount of an unacceptable variation with thepredetermined light intensity value, and wherein the light sensoracquires data corresponding to visible fluorescent radiation from thesurface of the object.
 15. The lighting system of claim 14, wherein theultraviolet radiation sources in the array deliver ultraviolet radiationto the surface of the object in short pulses.
 16. The lighting system ofclaim 14, wherein the controller includes an input component and anoutput component to allow a user to interact with the lighting systemand to receive information regarding the surface of the object and thetreatment thereto with the ultraviolet radiation sources.
 17. Thelighting system of claim 14, further comprising fluorescent sensors todetect fluorescent radiation reflected from the surface of the object,wherein the fluorescent sensors operate in a pulsed regime todifferentiate from fluorescent signals reflected from the surface thatarise from the irradiation by the ultraviolet radiation sources.
 18. Thelighting system of claim 14, wherein the array of ultraviolet radiationsources is configured for movement about the object, wherein themovement includes both translational and directional degrees of freedom.19. The lighting system of claim 14, wherein the controller comprises acomputer system including an analysis program which makes the computersystem operable to manage the ultraviolet radiation sources and thelight sensor, wherein the analysis program can enable the computersystem to operate the ultraviolet radiation sources to irradiate towardsthe object, process data obtained during operation, and store theobtained data.
 20. A lighting system, comprising: a set of ultravioletradiation sources configured to irradiate a surface of a light sensitiveobject with ultraviolet radiation with a wavelength range that includesultraviolet-A (UV-A) radiation and ultraviolet-B (UV-B) radiation,wherein each of the ultraviolet radiation sources operates in apredetermined wavelength range that includes at least one of a UV-Aradiation wavelength range or a UV-B radiation wavelength range, whereinat least one of the ultraviolet radiation sources includes a UV-B sourceconfigured to operate at a peak wavelength that is within the UV-Bwavelength range, and wherein at least one of the ultraviolet radiationsources includes a UV-A source configured to operate at a peakwavelength that is within the UV-A wavelength range; a set of visiblelight sources configured to irradiate the surface of the object withvisible radiation, wherein at least one of the visible light sourcesincludes a blue light source configured to operate within a blue lightwavelength range; a plurality of light sensors configured to measurelight intensity at the surface of the object, wherein each light sensormeasures light intensity in a wavelength range that corresponds to therange of wavelengths emitted from at least one of the set of ultravioletradiation sources or the set of visible light sources; and a controllerconfigured to control the irradiation of the object by the set ofultraviolet radiation sources and the set of visible light sources,wherein the controller directs the UV-B source and at least one of theUV-A source or the blue light source to irradiate the object at acorresponding radiation, wherein the controller controls the lightintensity over the surface of the object by adjusting operational powerof the ultraviolet radiation sources and the visible light sources as afunction of light intensity measurements obtained by the light sensors,the controller using the light intensity measurements to determinewhether each ultraviolet radiation source is illuminating the surface ofthe object with an intensity that has a variation that is more than 50%of a predetermined intensity value targeted for the surface, thecontroller adjusting the power of an ultraviolet radiation source and/ora visible light source in response to determining that the ultravioletradiation source and/or the visible light source is illuminating thesurface of the object with an intensity that has a variation that ismore than 50% of the predetermined intensity value targeted for thesurface, the controller adjusting the power of an ultraviolet radiationsource and/or a visible light source as a function of the variationbetween the light intensity generated from the source and thepredetermined intensity value targeted for the surface.